WASHINGTON (AP) — El Nino, nature’s chaotic climate agent, has formed in a warmed-up Pacific Ocean and is expected to grow to historic strength, meteorologists announced Thursday.

Experts said the El Nino, a natural warming cycle, should further heat a globe already warming from fossil fuel pollution and will likely turbocharge extreme weather across the planet. Meteorologists forecast it will rival — or exceed — a record El Nino that began in 1997 and helped trigger from heat waves, floods, droughts, tornadoes and wildfires.

The U.S. National Oceanic and Atmospheric Administration officially confirmed the existence of the El Nino, which is near the equator that affects weather patterns across the globe. NOAA’s announcement said there’s a 63% chance that the El Nino will get so intense this late fall and early winter that it “would rank among the largest El Nino events in the historical record going back to 1950.”

The warm, deep waters of an El Nino affect weather patterns by bringing “a lot of extra heat to the surface, fueling a lot of extreme events for a lot of places around the world,” said Clark University climate scientist Abby Frazier.

She said, especially in the Pacific, “it can get dire very quickly.”

United Nations Secretary-General António Guterres described El Nino as an “urgent climate warning.”

“El Nino conditions will pour fuel on the fire of a warming world,” Guterres said in a video message.

El Nino’s impacts spawn winners and losers

The weather pattern’s effects vary by region. El Nino often dampens — but doesn’t eliminate — activity, but increases it in the Pacific. So while the U.S. East and Gulf coasts may get a break, Hawaii and other islands are more in danger, Frazier said.

The drought-stricken Middle East could benefit, climate scientists said. Other places are looking at more danger. Parts of western South America — where the first El Ninos were noticed decades ago — often get heavy rain and floods, along with an extra warm summer. India faces more intense heat waves, while drought, wildfires and heat threaten Australia.

Northeastern Africa is likely going to get weather whiplash from intense drought to dangerously heavy rains, said Columbia University climate scientist and El Nino expert Muhammad Azhar Ehsan.

In the U.S., El Ninos can cause more intense storms with heavier rainfall in the South, but they also tend to generally benefit the U.S. agriculture industry, said Jon Gottschalck, operational branch chief at NOAA’s Climate Prediction Center.

Michael Ferrari, meteorologist and head of research at the investment research firm Moby, said conditions for grains and seed, especially soybeans, look favorable in 18 major growing states, but are more mixed when it comes to dairy and cattle.

The northern Rockies and Southwest — where there’s an “off the charts” — could get some strong summer rains, Gottschalck said. The biggest effect in the U.S. is often in the winter, when the south can get wetter and the Pacific Northwest warmer and drier.

But overall, temperatures raised by the weather pattern can dampen American economic growth, said Stanford climate economist Marshall Burke. Several climate scientists forecast that 2027 will be the hottest year on record because of lagging effects of this El Nino, which is expected to peak in the fall or winter.

“We have pretty clear evidence that the U.S. economy grows more slowly when temps are above normal,” Burke said.

Strong early signs

The weather extremes caused by an El Nino also depend on when it develops.

Usually El Ninos form in the summer, peak in the late fall or early winter, and peter out the next spring, scientists said.

However, Ehsan’s team forecasts that this El Nino will peak a month or two earlier based on strong early signs from recent weeks. Princeton University climate scientist Gabriel Vecchi said large El Ninos like these also tend to last longer.

The early indications — including warmer water pushing toward the surface of the Pacific — have been so strong and noticeable that forecasters have all been predicting the same ultra strong El Nino, Vecchi said, adding that El Nino forecasts often are all over the place at this time of year.

Scientists predict stronger El Ninos as the world warms from the burning of coal, oil and gas, Frazier and others said. But she said it is too early to say if this El Nino is part of that.

Even before it officially formed, this El Nino has gotten nicknames ranging from “super” to “Godzilla.”

“Instead of scared, we can ask people to be prepared,” Columbia’s Ehsan said

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What started in 2024 as the two-day Outside Festival at Civic Center moves to the Auraria Campus, expanding to three days of music, film, thought-provoking speakers and outdoors culture. Renamed Outside Days, the event is a production of Boulder-based Outside Interactive Inc., which owns two dozen media and service brands including Outside, MapMyFitness, Velo, Gaia GPS and Trailforks. Last year’s event attracted 35,000 attendees, nearly double that of the inaugural year.

Famed rock climber Alex Honnold and co-host Fitz Cahall will record an episode of their Climbing Gold podcast with ski mountaineer Jim Morrison in a discussion of risk and resilience. Honnold was the first to free solo Yosemite’s El Capitan. Morrison made an epic ski descent of Mount Everest last fall via the Hornbein Couloir on the mountain’s North Face.

Adrian Ballinger will discuss the future of Everest in an era of drones, helicopters, climate change, ski descents and speed-focused ascents. Ballinger has guided in the Himalayas for 25 years, including 10 Everest ascents.

National Geographic photographer Keith Ladzinski will describe what it takes to capture exceptional images in remote places. Ed O’Brien of Radiohead will discuss music, nature and creative renewal.

, curated in partnership with Mountainfilm, includes 11 titles. Feature films include Threshold, the story of Jessie Diggins, an Olympic champion in cross country skiing who struggled with an eating disorder at the height of her career; Surfilmusic, a documentary about Jack Johnson and his evolution from surfer to filmmaker to musician; No Hands is the story of the Schwinn Bicycle Company, an iconic brand dating back to 1895.

Short films include two documentaries about athletes with disabilities. Right to Risk takes viewers to the Adaptive Climbers Festival in Kentucky’s Red River Gorge, while The Best Day Ever focuses on two adaptive mountain bikers in Vermont’s Green Mountains. Another short, The Boys of Summer, is the story of a group of teenage boys and the emotional growth they experienced at a remote summer camp in the woods of Vermont.

For , Friday’s headliner will be Death Cab for Cutie plus Goth Babe and Japanese Breakfast. Saturday’s lineup includes My Morning Jacket and The Flaming Lips. The lineup on Sunday includes Cage the Elephant and two local bands, N3ptune and The Mañanas.

A can be found on the Outside Days website. 

As the Colorado River and its once massive reservoirs shrink from overuse and climate change, officials are faced with a decision that pits conservation against ratepayer costs for electricity.

To fight off predators of the humpback chub, a threatened fish native to the river, Glen Canyon Dam in northern Arizona would need to do what is known as a “cool mix flow,” where cold water is released from deep in its reservoir to cool the river below. But there are no hydropower turbines in the cool, deep section, so significant power generation would be lost.

The proposal comes after the  on record for the Colorado River Basin, relied upon by farmers, industries, wildlife and more than 40 million people in seven U.S. states, tribal nations and Mexico. It also comes as those states fail to reach a  on how to share the river’s dwindling resources beyond this year, when the guidelines expire.

“There is a limited water supply. It����ap getting even lower. And with that, a lot of hard decisions need to be made,” said John Berggren, regional policy manager for the environmental nonprofit Western Resource Advocates.

Utilities that buy this hydropower say the cool water releases would be costly because they would have to spend millions to buy alternative energy and would increase financial hardship for customers. But supporters say that without cool releases, the warm waters projected downstream this summer would allow non-native predatory fish to spawn, further threatening the , and would destroy a world-famous ���Ա𲹰�����.

The Bureau of Reclamation, which is expected to announce a decision in the next couple of weeks, said in a statement that it is weighing several factors including the ecological health of the river and the hydropower production of the dam. The Interior Department, which oversees the bureau, declined to comment. If the cool water release is approved, it would likely happen from June to October through jet tubes, bypassing the turbines near the warmer surface.

How mixing cool water protects fish

Lake Powell, one of two massive reservoirs on the Colorado River, is just 23% full after decades of overuse and evaporation of water as average temperatures rise because of climate change. A record low inflow is expected this summer. With such a low reservoir, warm water near the surface gets sucked through the generators and sent downstream.

Smallmouth bass, introduced in Lake Powell in the 1980s for sport fishing, live at that warm surface, and also get sucked through the hydropower generators and into the river below. That’s a problem for the humpback chub and other federally protected fish in the Grand Canyon, a 278-mile (447-kilometer) stretch farther south on the river that’s world-famous for its geologic formations. ���� shows that roughly half the bass survive the generators. If the river below is warm enough, they spawn.

Smallmouth bass already feast on humpback chub in the river’s upper section, where agencies spend millions of dollars annually to keep the intruders in check. Native fish have been safer below Glen Canyon Dam because it blocks the path to the Grand Canyon — but that may not be true for long.

Water temperatures just downstream of the dam are expected to shatter records set in 2022, when smallmouth bass were . Officials project that water will consistently exceed 60 degrees Fahrenheit (15.5 Celsius) by mid-June due to the warm water being pulled in from Lake Powell. Any higher than that, and non-native predatory fish that pass through the dam could reproduce.

Officials say cool water releases from Lake Powell in 2024 and 2025 successfully prevented spawning.

It����ap critical to consider the cost of not doing the cool mix, Heather Whitlaw, field supervisor with the U.S. Fish and Wildlife Service, said during a recent meeting on managing the issue. “We are certainly just giving up on the future for any kind of recovery for humpback chub and all of the other pieces of the system that rely on those cooler water temperatures.”

With no long-term solution to keep the predators from passing through the dam, withholding cool water would force officials to rely solely on manually removing them downstream.

More hydropower loss could further impact utilities

Utilities reliant on hydropower from federal generators are worried.

If the cool water releases are approved, it could mean bypassing about half the generation at Glen Canyon Dam, forcing utilities to buy power elsewhere that would likely be more expensive, according to the Utah utility group Heber Light & Power.

“We keep hearing comments that we must continue Cool Mix because the cost of not doing it will be even greater,” the Colorado River Energy Distributors Association, which represents about 155 customers who buy federal hydropower generated from the river and opposes the releases, said this month in a letter to Interior Secretary Doug Burgum. “We would like to understand what remediation would consistently cost more than $20 to $30 (million) per year.”

The association said the releases are not a sustainable solution to prevent smallmouth bass from reproducing and threaten a critical fund used to operate, maintain and invest in hydropower and transmission facilities.

During the cool water releases in 2024, nearly 900,000 acre-feet of water bypassed the generators, costing $19 million in replacement energy costs, according to the Bureau of Reclamation. It����ap unclear how much water would bypass the generators this year, although the cost to replace it is anticipated to be around $25 million — roughly the total cost to hydropower users from the prior two years.

The ongoing loss of hydropower due to Lake Powell’s decline has brought challenges to Heber Light & Power as the population grows, said Emily Brandt, the utility’s energy resource manager. The overall decline has led to rate hikes the past five years.

Ann Moulton, who lives in Heber City, has seen her residential electricity bill from Heber Light & Power steadily rise. Her bill this April was $125.98, up from $103.24 and $86.14 for the same month in the previous two years. That’s impacting her budget, she said.

Other customers are struggling to pay. So far this year, the utility has seen a jump in late payments over the past two years, from 10% to 12%.

Brandt said the utility supports caring for fish, “but this particular experiment seems unnecessary.”

“We’re already seeing reduced generation from drought, and now we’re seeing even further reduced generation because of this environmental experiment,” Brandt said.

Fisheries downstream are also in limbo

Dave Foster still remembers the 2022  in Glen Canyon, a remote stretch of river between the dam and the start of the Grand Canyon. Warm water killed nearly half the rainbow trout the world-renowned fishery relies on, said Foster, who has been working on or around that stretch of river since age 13.

He and other guides are still recovering from the die-off, he said, as “the population has simply not rebounded.” But cool water releases in recent years have offset more negative impacts, and more this year would get them through the fall and winter.

Foster has warned customers booking trips after mid-June that he might cancel if the water gets too warm, which can stress fish. Without cool water releases this year, “that’s it for the trout fishery,” he said. “There’s no ambiguity about it. It will destroy it.”

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In the third to last paragraph, corrects the name of a stretch of the river to Glen Canyon instead of Marble Canyon.

���� that is forecast to get quite strong will likely dampen the upcoming Atlantic hurricane season, but it won’t make the potentially deadly storms disappear, federal and outside meteorologists predict.

The National Oceanic and Atmospheric Administration on Thursday issued its seasonal outlook for the Atlantic, giving a 55% chance of a below-average season. The agency forecasts eight to 14 named storms, with three to six of them becoming strong enough to hit hurricane status and one to three of those intensifying to major hurricanes.

A normal hurricane season has 14 named storms, seven of them becoming hurricanes and three of them reaching major hurricane level, which is more than 110 mph.

Eighteen other groups, private and academic, have also forecasted what they think the season will be like and most of them also call for a below average summer and fall. Those  average a dozen named storms, only five becoming hurricanes and two of those being major ones. Those forecasts also call for the Accumulated Cyclone Energy index, which takes into account strength and duration of storms, to be 80% of normal.

Colorado State University, which pioneered the science of hurricane seasonal forecasting in 1984,  the lowest overall activity since 2015, which was the strongest El Nino in the last 75 years. And that forecast is likely to be revised to even lower numbers in June, said Colorado State’s hurricane expert Phil Klotzbach.

This is after nine of the last 10 Atlantic hurricane seasons have been above normal or even hyperactive, Klotzbach said. Last year , but then had a burst, producing a near-record total of three Category 5 hurricanes, including  and Cuba, said Suzana Camargo, a climate scientist and tropical weather expert at Columbia University.

Inflation-adjusted damage across the globe from tropical cyclones has increased from an average of $11.4 billion a year in the 1980s to $109.7 billion a year over the past 10 years, with three-quarters of the damage done in the Atlantic, Gulf of Mexico and Caribbean, according to insurance giant Munich Re.

Hurricanes, typhoons and cyclones are the same weather event, with the different names being used in different parts of the world.

“We should expect a less active year than certainly what we’ve seen recently, and perhaps significantly so below average,” said University at Albany atmospheric scientist Kristen Corbosiero. “But again, it only takes one to cause real devastation and destruction in the mainland U.S. or even in Hawaii.”

El Nino decapitates Atlantic storms

It’s mostly because of “the elephant in the room” which is an , Camargo said.

An El Nino is the natural and cyclic warming of parts of the central Pacific that warps weather patterns around the globe, especially during winter. Scientists for decades have found a correlation between an El Nino and below average Atlantic hurricane activity and stronger and more storms in the central and eastern Pacific. This year many forecasts are calling for a strong, super-strong or even record setting intense El Nino. During a , the cool flip side of El Nino, the Atlantic is generally busier with stronger storms.

There’s a 98% chance that there will be an El Nino this summer and an 80% chance it will be moderate or strong, NOAA Administrator Neil Jacobs said Thursday.

Atlantic hurricane seasons when an El Nino reaches strong or very strong status have two-thirds the named storms and half the hurricanes of the 1991-2020 average, according to an Associated Press analysis of storm and El Nino statistics.

El Ninos fight Atlantic storm formation in several ways, especially with cross winds about 1 mile to 7 miles above the surface “which can basically blow apart the thunderstorms that make up” a hurricane, Corbosiero said.

“A stronger than normal wind shear tends to tilt storms as they try to develop,” said University at Albany atmospheric scientist Brian Tang. “It pushes dry air into storms. And prevents storms from developing in the first place. And if they do develop, it also prevents them from intensifying.”

El Nino reduces the number and intensity of weaker storms, but once a storm hits hurricane status with 74 mph winds, “they can be kind of like a self-feeding entity” and are less prone to being dampened by El Nino’s wind shear, said Matthew Rosencrans, lead hurricane season forecaster with NOAA’s National Weather Service.

Forecasts for peak hurricane season show strong wind shear from the west in the main development region for the largest and long-lasting hurricanes that come off of Africa and develop as they head west over the Atlantic, Klotzbach said. Fewer of these type storms happen during El Ninos.

In the 15 strongest El Nino years since 1950, 37 named storms, 11 hurricanes and three major hurricanes made landfall on the continental United States, but in the 15 coldest La Nina years 61 named storms, 31 hurricanes and 10 major hurricanes hit America’s Gulf and Atlantic coasts, according to Klotzbach. He said El Nino shrinks the number of hits on the Atlantic coast, but has less of an influence on the number of Gulf coast landfalls.

In addition to El Nino, dry conditions in Africa and water in the Atlantic being only slightly warmer than normal contribute to the forecast of a weaker season, Rosencrans said.

Opposite effect in the Pacific

El Ninos and La Ninas have the opposite effect on storms in the central and eastern Pacific as they do in the Atlantic, so experts are expecting a busier season in those regions. Jacobs said there’s a  that the eastern Pacific will have an above normal season.

NOAA forecasts 15 to 22 named storms in the Pacific with nine to 14 becoming hurricanes and five to nine of those being major hurricanes. Average is 15 named storms, eight hurricanes and four major hurricanes. Rosencrans said the main area of central Pacific storm development shifts closer to Hawaii during El Ninos.

Eastern Pacific storms near Baja Mexico tend to “go west, affect the fishies and little else,” Corbosiero said. But at times they can turn east or north and cause massive damage as in  in 2023 that smashed into Mexico, or 1992’s Hurricane Lester, which caused heavy rains in the U.S. Southwest, she said.

Hawaii is a small island chain in a big ocean that can be threatened. In 1992, an El Nino year when there were few Atlantic storms (though Miami was devastated by  ), Hawaii was hit by 

Further west toward Asia and India, “your odds of any storm forming becoming a super typhoon go up significantly in El Nino,” Klotzbach said.

The eastern Pacific hurricane season started May 15 and the Atlantic season begins June 1 and both end Nov. 30.

El Ninos can also make hurricane season longer, said John Bravender, a weather service meteorologist in Honolulu. “With the warmer waters across the area, not only can hurricanes maintain their strength at higher latitudes, but also longer through the year,” he said.

The state is preparing for hurricanes just as parts of Hawaii are still reeling from recent back-to-back storms that caused , Gov. Josh Green said.

The Associated Press’ climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Find AP’s  for working with philanthropies, a list of supporters and funded coverage areas at .

WASHINGTON (AP) — Scientists are jettisoning their worst- and best-case scenarios for a warming world as no longer plausible. That shows how modest gains in the fight to curb climate change have dialed back the most catastrophic of future heating but also confirmed that there’s no chance to limit warming to the international goal set in 2015.

Researchers’ new list of seven plausible carbon pollution scenarios for the future are pushing aside two staples of climate policy: the extremes on either end.

The extremes have become less probable in the past several years because of how we power our world. Carbon dioxide, released from the burning of gas, oil and coal, is chiefly responsible for warming. Increasing use of green energies, like solar, wind and geothermal, which don’t emit carbon dioxide, have lowered top end carbon pollution projections. However, because those changes haven’t been fast enough, the bottom end projections have risen.

The set a goal of limiting warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) since pre-industrial times, or the mid-1800s, giving rise to the mantra but now scientists say that even their best-case scenario still shoots past that signature temperature mark. On the other end, those same new scenarios no longer include the coal-heavy future that would lead to 4.5 degrees Celsius (8.1 degrees Fahrenheit) of warming by 2100, a scary scenario that many scientific studies used in their future projections.

The new proposed worst-case scenario has an end-of-the-century warming of about 3.5 degrees Celsius (6.3 degrees Fahrenheit), a full degree (1.8 degrees Fahrenheit) less than the old scenario, while the updated best-case future is a couple tenths of a degree Celsius (0.36 degrees Fahrenheit) warmer than previously theorized, squeezing past the Paris goal, said climate scientist Detlef Van Vuuren of Utrecht University, lead author of a recent

“There is kind of a narrowing of the futures. It cannot be as bad as we thought, but it cannot be as good as we hoped,” said Johan Rockström, director of the Potsdam Institute for Climate Impact Research in Germany.

The scenarios include a “middle” one where by the end of the century the world warms 3 degrees Celsius (5.4 degrees Fahrenheit) above pre-industrial times, which is roughly the path society is currently on, scientists said. The world is now about (2.3 degrees Fahrenheit) above pre-industrial times. Even tenths of a degree of warming cause problems for Earth’s ecosystems, as species die off, fresh water becomes more scarce and extreme weather events, such as flooding and heat waves, intensify.

It����ap too late to keep below 1.5 degree goal

Because carbon pollution keeps rising globally and stays in the atmosphere for about century, the best-case scenario is for warming to shoot past the 1.5 degree mark, peak at 1.7 degrees Celsius (3.1 degrees Fahrenheit) for maybe as long as 70 years, and eventually somehow come back down below 1.5 degrees if a technology can be designed to remove massive amounts of carbon from the air, said nine of the 10 scientists interviewed for this article. The world is warming at a pace of a tenth of a degree Celsius (nearly 0.2 degrees Fahrenheit) every five years, they said.

“This is just physics,” said climate scientist Bill Hare, CEO of Climate Analytics, a policy institute. “We’re losing the ability to limit warming even by two degrees without strong action and people need to be aware of that and be aware that it����ap a political failure. It����ap not an act of God or anything. It is just because politicians in many places are not acting fast enough.”

The 1.5 goal is not just a number, said Cornell University climate scientist Natalie Mahowald, co-author of a detailing the harms of going higher than 1.5 degrees.

“There’s a lot of implications for, you know, not being able to meet the 1.5. And, of course, the people who will suffer the most are on the small island developing states,” Mahowald said. “Some of them will go underwater.”

Highest warming scenario changes spark debate

American Enterprise Institute’s Roger Pielke Jr. said changes to the highest end scenario matter because it was presented as a likely future that could come true if nothing changed. Thousands of scientific studies have been based on that highest warming scenario, called RCP8.5, even though research had already shown it to be improbable.

“It was always presented as where we were headed absent explicit climate policy,” even though it was based on out-of-date and incorrect coal-heavy energy theories, Pielke said in an email.

Keywan Riahi, lead author of the that introduced that scenario, said when it was designed the high-end case was not where scientists thought the world was heading.

“It was never a likely case. It was basically, given the underlying studies in the literature at that time, a plausible higher bound of what possible emissions could look like. This is very different than if you would ask the question, what is now the most likely scenario,” said Riahi who is director of the Energy, Climate and Environment Program at the International Institute for Applied Systems Analysis in Austria.

It����ap a success story, said Riahi, because “in the last 10 years or the last 15 years, the cost of renewables, particularly solar and wind, have fallen by almost 90%.”

President Donald Trump jumped into the fray with a social media post saying: “GOOD RIDDANCE! After 15 years of Dumocrats promising that ‘Climate Change’ is going to destroy the Planet, the United Nations TOP Climate Committee just admitted that its own projections (RCP8.5) were WRONG! WRONG! WRONG!”

“The risks of climate change have not disappeared,” responded study author and scientist Van Vuuren. “The good news is that we did not follow the most dramatic emission pathway. However, we are still heading towards a future with significant climate impacts; a future we should avoid.”

A big asterisk looms

While the upward curve of emissions is flattening, there’s a factor that could still make the older high end temperature estimates come true, Mahowald, Rockstrom and Hare said. That����ap because the newest batch of scenarios only look at emissions from the burning of fossil fuels, which is the control knob that humans can turn.

Nature has another knob of its own referred to as climate feedbacks, which humans don’t control. Scientists have had a hard time projecting climate feedbacks, and that can add another half a degree Celsius (nearly a degree Fahrenheit) of warming on top of what����ap caused by emissions.

Those feedbacks include release of massive amounts of heat-trapping carbon now being stored in the world’s oceans, in forested areas and in the Amazon, along with changes to ocean currents and cloud reflectivity, Rockstrom said.

The Associated Press’ climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Find AP’s for working with philanthropies, a list of supporters and funded coverage areas at .

Seasonal models are predicting an El Nino climate pattern that could be the strongest on record, bringing with it more extreme weather.

“I think we’re going to see weather events that we’ve never seen in modern history before,” WFLA-TV Chief Meteorologist and Climate Specialist Jeff Berardelli, in Tampa, Florida, said Friday.

An is expected to develop from the middle of this year, impacting global temperature and rainfall patterns, according to the World Meteorological Organization. While the models indicate that this may be a strong event, the WMO cautioned that the models also have a harder time making accurate forecasts in the spring.

What El Nino is

of patches of the equatorial Pacific that then alters the world’s weather patterns. Its counterpart, La Nina, is marked by waters that are cooler than average.

Berardelli said an El Nino event essentially redistributes heat on Earth. Currently, the subsurface heat in the Pacific is moving east across the ocean and ascending to the surface from the deep waters, the initial stages of El Nino.

The showed that sea-surface temperatures are rising rapidly. There is high confidence in the onset of El Nino, followed by further intensification in the months to follow, according to Wilfran Moufouma Okia, chief of climate prediction at WMO.

El Nino typically occurs every two to seven years and lasts around nine to 12 months, WMO said.

Why it����ap causing alarm

It looks like the predictive models are onto something, said California Institute for Water Resources climate scientist Daniel Swain. That is because the volume and the intensity of the subsurface warm water anomalies — or pulses of unusually warm water that are a key part of El Nino physics— are about as large as we’ve seen in the historical record, he added.

The very strongest events are called “super El Ninos.”

“One of the key building blocks to make it fully materialize is, in fact, occurring,” Swain said Friday. “We still don’t know exactly what����ap going to happen. It����ap not guaranteed it’ll be a super El Nino. But the potential is there for something genuinely remarkable.”

If the Pacific releases a lot of heat, it supercharges the climate system and wreaks havoc weather-wise, Berardelli said. With more heat, there will be stronger heat waves, worsening drought in some areas, but also more moisture in the air that leads to more intense floods, he said.

El Nino also subdues the hurricane season in the Atlantic because there is so much heat in the Pacific that outcompetes the Atlantic, Berardelli added. Places like the Caribbean will be extra dry this summer and likely have fewer tropical systems, he said.

Where we may see the impacts

El Nino has global impacts. Across the United States, it looks like this summer will be hotter than normal, with significant heat waves, Berardelli said. While the specifics are hard to pinpoint this far out, Berardelli is also expecting to see more frequent daily thunderstorms in the Southwest U.S.

Forest degradation, driven by wildfires, logging and drought, . This could be exacerbated in 2026 with a strong El Nino.

The excess heat brought to the surface by El Nino, combined with the planet����ap warming due to climate change, will lead to record-breaking global warmth, Swain said. He expects to see record global warm temperatures later this year, next year or both.

“All indicators are, at this point, that the next year is going to be a pretty wild year from a global climate perspective,” Swain said.

Michael Mann, a University of Pennsylvania climate scientist, said that while El Nino boosts global temperatures a bit for a year or two, it����ap basically a “zero-sum game.” It typically oscillates back toward La Nina, which in turn lowers global temperatures for a year or two, he added. The thing to worry about is the longer-term, steady warming trend that will continue as long as people continue to burn fossil fuels, Mann said Friday.

Associated Press News Director Peter Prengaman contributed to this report.

The Associated Press’ climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Find AP’s for working with philanthropies, a list of supporters and funded coverage areas at .

A council meant to  proposed Thursday a series of long-awaited changes to the disaster recovery body that stop short of the administration’s promises to dismantle it, but could reduce the number of disasters the federal government supports and the amount of money it doles out.

The council appointed by President Donald Trump approved a highly anticipated report that  and outlines ways the Trump administration could potentially put far more responsibility on states, tribes and territories for .

It proposes upending how the federal government determines which disasters to support, how FEMA pays states and other governments for disaster recovery costs, and what kind of FEMA assistance survivors receive, among other reforms. Nearly 6,000 attendees watched the meeting virtually.

“These recommendations are all about accelerating federal dollars, streamlining the process, making it less bureaucratic so that Americans can get the help they need on the worst day of their lives,” said former Virginia Gov. Glenn Youngkin, a council member.

Homeland Security Secretary  said in the council’s meeting on Thursday that the report offered him “a clear direction and an oversight of an agency that is in need of reform, but is still mission capable.”

The recommendations will now be sent to Trump, though many of the reforms would require congressional action.

The White House did not immediately respond to questions about whether Trump endorses the recommendations or what actions the administration might take next.

Major changes to how states and survivors receive aid

Among the council’s most significant recommendations is a proposal to change how states, tribes and territories receive federal support after disasters.

FEMA currently reimburses states and others after disaster recovery work is done, at a minimum cost share of 75%. It proposed changing that to an upfront payment model where states receive money within 30 days of a disaster, with a potential for another payment further down the line if costs far exceed initial estimates.

Which disasters qualify for federal support would also change. Major disaster declarations are at the discretion of the president, but are informed by FEMA damage assessments and a per-capita formula that weighs costs against local population. The council recommends instead establishing a “parametric threshold,” in which a pre-defined set of metrics for a disaster can trigger federal support.

Survivors would also see major changes to how they receive FEMA aid. The council proposed offering survivors a one-time payment instead of offering multiple channels of rental, repair and replacement assistance, and limiting housing assistance to those whose homes are rendered uninhabitable.

FEMA would focus its survivor aid on emergency housing, and move away from long-term housing assistance, giving states the options to run their own housing programs while adhering to federal standards.

“States, figure it out,” said council member and Florida emergency management director Kevin Guthrie. “Do what����ap best for you.”

Other recommendations include shifting most flood insurance policies away from the National Flood Insurance Program, which is over $20 billion in debt, to the private market, and continuing to align premium costs more closely to risk.

A bumpy road to a final report

Trump created the FEMA Review Council by  shortly after his second term began, on the same day he  after touring destruction wrought by Hurricane Helene in North Carolina. He has threatened to dismantle the agency and has repeatedly said he wants to push more responsibility for disaster preparedness, response and recovery to the states.

The 12-person council is co-chaired by Mullin and Defense Secretary Pete Hegseth. It is made up of current and former officials and emergency managers from predominantly Republican-led states.

Emergency managers, local leaders, nonprofits involved with disaster management and survivor groups have anxiously awaited the council’s report, which was due roughly six months ago but was delayed as former Homeland Security Secretary Kristi Noem and council members .

Noem, who was widely criticized for  to states, �����Ի��� in March.

The final recommendations seemed to move away from at least one of the most controversial reforms included in past drafts: Cutting the FEMA workforce by 50%, a recommendation included in a December draft reviewed by The Associated Press.

As a yearslong stalemate in negotiations persists between the seven states that share the river, it’s become increasingly likely that the federal government will impose its own long-term plan, choosing from a range of proposals officials have outlined in recent months.

But experts and water managers across the 250,000-square-mile Colorado River basin are raising the alarm about the five plans, questioning if any of them hold up under the new climate reality. They say the federal plans won’t keep the system from crashing in critically dry years — which are becoming more frequent — and could wreak chaos on the pivotal lifeline for 40 million people in the American Southwest.

“In every one of those alternatives, under what they call critically dry hydrology, the system is failing,” said Andy Mueller, the general manager of , a taxpayer-funded agency based in Glenwood Springs that works to protect Western Slope water. “And critically dry hydrology is what we have continued to see consistently in the basin in the last 25 years and what we should expect going forward.”

Climate change and persistent drought have already sapped hundreds of billions of gallons of water from the river’s annual flow. Officials from the U.S. Bureau of Reclamation Friday to add more water to Lake Powell — one of the system’s two major reservoirs downstream of the river’s headwaters in the Colorado mountains — after updated projections showed that spring flows into the already-low reservoir could be less than a third of average.

Federal water managers over the next year will release hundreds of millions of gallons of water from Flaming Gorge Reservoir in Wyoming and Utah to keep Lake Powell above “minimum power pool” — the reservoir elevation needed to send water through hydropower turbines. Without access to the turbines, water released from the dam must flow through much smaller bypass tubes that are , choking flow from one of the West’s largest water banks.

Emergency decisions like those taken Friday illustrate some of the risks of failing to prepare for intense drought, experts say.

In extremely dry years, the longer-term plans under consideration by Reclamation would allow the water levels of the system’s two main reservoirs to repeatedly fall below minimum power pool. Federal officials then would be forced to make recurring emergency cuts to the water supplies of the three states downstream of the reservoirs, creating uncertainty for millions of people and a massive agricultural industry.

For more than two years, negotiators from the seven states that rely on the river have tried and failed to agree on that runs from Colorado’s high country to Mexico. The technical nitty-gritty of the disputes is wonky, but the key issue underlying the schism between the states is simple: Who should be forced to use less water — and how much less — as the Colorado River’s flows shrink?

Reclamation officials on Friday said they are preparing to implement their own plan this summer if the states can’t agree on answers to those questions. In January, federal officials released five potential operational guidelines — called “alternatives” in federal jargon — and asked for input.

They , including critiques from across the basin asserting that none of their plans would function well in dry years. That criticism also applied to the only plan the Bureau of Reclamation can implement without consensus from the basin states or without gaining new legal powers.

Letters from a number of Colorado entities — including the , , the Western Slope’s and county commissions from a vast swath of the state — urged federal officials to present at least one plan that would hold up in extremely dry years.

“Sound science dictates that Colorado River management must evolve to handle a permanently drier future,” Tina Bergonzini, the general manager of the Grand Valley Water Users Association, . “The current federal preference for predictability is an atmospheric impossibility given that studies indicate rising temperatures have already slashed river flows by a fifth.”

Bureau of Reclamation officials declined an interview request for this story. But they have publicly acknowledged the risk.

“In critically dry periods, all of the alternatives have unacceptable performance,” bureau engineer Rebecca Smith said during . Even imposing large cuts to water usage in those years would not keep the major reservoirs at functional levels, she said.

The conflict on the Colorado is likely one of the world’s first major water policy overhauls to grapple with the reality of climate change, said , a senior water and climate research scholar at Colorado State University’s .

In the past, Colorado River managers made operational tweaks and short-term deals to address drought. This time, it’s different.

“We’re not looking at an incremental step here,” Udall said. “We’re looking at a complete redo of how we operate this resource that affects 40 million people.”

‘Downright scary what����ap going on’

The West first wrestled with divvying up the powerful Colorado River in 1922, when delegates from each of the seven states met in Santa Fe and signed .

At its most basic, the compact divides up the 18 million acre-feet of water then estimated to be in the river — including 7.5 million acre-feet reserved for the Upper Basin states of Colorado, Utah, Wyoming and New Mexico, and 7.5 million acre-feet for the Lower Basin states of California, Arizona and Nevada. An acre-foot of water is the volume of water it takes to cover an acre of land in a foot of water — about 326,000 gallons — and is generally considered the annual water consumption of two families.

The 18 million acre-feet was likely an overestimation of how much water there was even a century ago, but today’s river provides even less than the total amounts promised to states in 1922.

“Since 2000, the flows have been radically different,” Udall said.

The 20-year average annual flow measured in 1925 was 17.6 million acre-feet, Bureau of Reclamation data show. In 2025, it was 12.7 million acre-feet.

But even that number hides the reality of recent dry years. The five-year average amounts to only 10.9 million acre-feet. Last year’s flow measured at 8.5 million acre-feet.

This year will be even lower due to record-low snowpack across much of the basin.

The conditions this year are not a one-off, Udall said, but symptoms of a larger warming trend fueled by human-caused global climate change. Hotter temperatures not only increase water loss through evaporation but also make plants and soils thirstier, reducing the amount of water that flows downstream. Evidence is also piling up indicating that climate change is reducing precipitation across the Colorado River’s headwaters, Udall said.

“I think this is quite nerve-racking — and perhaps just downright scary — what����ap going on,” he said.

The Bureau of Reclamation acknowledges the likelihood of a hotter, drier future in its draft environmental impact statement, though it shies away from using the term climate change.

“The basin is experiencing increased aridity due to climate variability, and long-term drought and low-runoff conditions are expected in the future,” the document’s executive summary states.

Expect more critically dry years

Future hydrology is the biggest and most impactful uncertainty federal officials must reckon with while crafting plans for the river, Smith said in the January webinar.

The bureau modeled hundreds of potential future conditions and then compared how each of its five proposed plans would perform under different levels of river flow over the next 20 years, broken into three categories:

• Average (12-14 million acre-feet average over 20 years)
• Dry (10-12 million acre-feet average over 20 years)
• Critically dry (less than 10 million acre-feet average over 20 years)

If average flows over the next two decades fall in the “average” category, the plans generally would be able to keep Lakes Powell and Mead — the two big downstream reservoirs — above critical levels and eliminate the need for emergency reductions in water supplies to keep them functional.

But that’s not how recent years have gone.

Since 2020, Colorado River flows have fallen into Reclamation’s “critically dry” category in four of six water years. The repeated dry years, coupled with downstream consumption that has not changed to match the reduction in inflow, have and Mead, which are now less than a third full.

“Critically dry hydrology is what we have continued to see consistently in the basin and what we should expect going forward,” said Mueller, from the Colorado River District.

Between 2021 and 2025, the river’s flows averaged 11.2 million acre-feet — low enough to fall into Reclamation’s dry hydrology category. That average was boosted by the unusually wet 2023 year when the river delivered 17.4 million acre-feet of water, while most of the other years fell into the critically dry category.

As modeled by the bureau, if critically dry years continue, Powell and Mead will more often fall so low that their will become unusable, impacting power availability for more than 1 million people. Bureau officials would more often be forced to implement emergency water cuts to try to keep the reservoirs functional.

In , the Colorado River District urged officials to add an alternative plan that would function well in critically dry periods.

“The population of the state of Colorado and the entire Colorado River basin is best served by the Department of the Interior studying alternatives that actually bring the system into balance,” Mueller said, referring to the cabinet department above the bureau. “And recognizing that those management alternatives will have some extremely harsh realities — hydrologically and politically — up and down the basin. But that����ap what we’re best served by.”

Bureau of Reclamation’s most likely plan

Without a deal between the seven states or obtaining more legal authority from Congress or the states, federal officials will be forced to implement a plan dubbed “Basic Coordination.”

The plan mandates the least cuts for the Lower Basin states and is generally less flexible than the other proposals.

In dry periods under that plan, Lakes Powell and Mead could fall below minimum power pool 30% to 40% of the time, according to Bureau of Reclamation projections. In critically dry periods, that figure rises to more than 70%.

The federal agency estimates that Lake Powell will be vulnerable to falling below that level in the first five years under the Basic Coordination plan if the average annual flows in that period amount to less than 11.3 million acre-feet. The five-year average has fallen below that level in three of the last five years.

If the federal government enacts the Basic Coordination plan, the bureau will keep scrambling to make emergency decisions to ensure Powell and Mead are operable. Such decisions could involve cuts to Lower Basin water supplies or the sending of water from federally-managed reservoirs upstream — like Flaming Gorge or Colorado’s Blue Mesa — to keep enough water in Powell.

Federal officials could also seek water from other water sources the government owns or operates in Colorado, Mueller said, such as from irrigation projects on the Western Slope or , which delivers Colorado River water across the Continental Divide to northeastern Colorado.

“Legal uncertainty and hydrologic uncertainty would erupt,” he said. “We, as good water managers throughout our state and the basin, should try to avoid that.”

Under the Basic Coordination plan, reactive chaos will erode what certainty remains on the changing river, said , the regional policy manager for , a climate advocacy organization.

“We will be right back where we are with emergency operations,” he said, like pulling water from upstream reservoirs to prop up Powell. “But you can’t do that every single year because there isn’t enough water in the Upper Basin reservoirs.”

Bureau of Reclamation officials plan to finalize new long-term guidelines by Aug. 15, in time for the Oct. 1 start to the new water year, which generally tracks with the start of snowfall.

“You don’t want to limp through with Basic Coordination, you’d want to put everything on the table you can,” Berggren said.

“We’re facing a crisis,” he continued. “We have tools available, we know what they are — we just need to implement them.”

Water scarcity, due to exceptionally low mountain snow and soil-drying heat, looms foremost.

“If we don’t get moisture, I’m not going to plant,” said chile grower Praxie Vigil, who runs along the Bessemer Ditch, a 43-mile irrigation canal that once nourished crops across 20,000 acres east of Pueblo. He was planning to decide this weekend.

“It����ap not looking good for any of us. Usually, I just plant and hope for the best. But this year, I’m not going to. This is bad. I can barely water 20 acres,” said Vigil, who works a side job as a pipe-welder to make ends meet.

The dry conditions, compounded by federal policies and turbulence far beyond the Rocky Mountain West, are forcing Colorado farmers to scale back production this year, change the crops they prioritize and question their long-term survival. Grocery shoppers likely will see less locally grown food in produce sections.

First, the Trump administration’s tariffs and war on Iran drove up prices for fertilizer, packaging and other materials. The Mideast conflict also broke supply chains — sprinkler heads and filters needed for those peaches, made in Israel, aren’t available.

Then, Trump’s bombing that began Feb. 28 led to fuel costs spiking to $5 per gallon of diesel.

Meanwhile, the federal government’s crackdown on immigration and state limits on how many hours seasonal foreign workers with H2A visas can work have intensified agricultural labor uncertainty.

“I haven’t had anybody physically taken away. But there’s definitely fear among the workers,” Brian Crites said at , working his family’s 1890s homestead at Avondale, where he’ll leave 750 of his 1,000 acres unplanted due to high costs and lack of water. Even though workers from Mexico on his farm hold green cards, they see information online, Crites said. “I try to keep the morale up. I tell them they’re pretty safe here.”

Other challenges include retailers mislabeling produce as Colorado-grown when it’s not, which degrades the state brand. Lawmakers and Gov. Jared Polis just prohibiting the deceptive trade practice of fake local labeling.

“Agriculture is a big powerhouse of our economy. It is our No. 1 export sector. We do everything we can to support ranchers and farmers in our state,” Polis said in an interview last week. “What the government cannot do is make it rain or snow.”

‘Hit from every direction’

As summer approaches, “everybody’s looking at what their options are,” said peach grower Bruce Talbott, operator of on Colorado’s Western Slope.

His orchards depend largely on the federally run Green Mountain Reservoir, which measured 36% full last week, with streams feeding the reservoir also running low because paltry mountain snowpack had already melted away.

“We want to haul down as little water as possible and stretch what we do have as far as we can. How that����ap going to play out is unknown. …We’ve never actually shut off the canals. Right now, we’re running them low,” Talbott said.

“If there’s no more capturable water, then we’ve got enough until Aug. 1.” he said. “That����ap enough that about half the peaches would get harvested. The last half would not. The peaches would be small. And it would be awfully hard on trees. Our chances of having healthy trees headed into next year would be very compromised. We’d probably lose a lot of orchards.”

Hail this month damaged cherries, pears and apricots in the area, and crops that bloomed early in February due to warm winter temperatures need water longer and still are vulnerable to frost through May, director Jessica Burford said.

“We’re getting hit from every direction,” she said. “It’s going to be a very expensive year. Farmers are worried about our peaches being large enough to meet grocery store standards.”

Yet few were quitting.

“We are farmers. We are here to produce food. If we don’t do it, we won’t get paychecks. We would starve, our fields would go to crap, and weeds would take over. So we might as well give it a shot,” said Dalton Milberger, owner of , east of Pueblo. “Chile is our lifeline.”

As Milberger was preparing to plant chile seeds last week, his machine broke down.

A statewide crisis

Farmers statewide are wrestling with similar difficult decisions on whether to plant crops, Commissioner Kate Greenberg said.

The unprecedented warm weather has led to “an incredible lack of soil moisture,” and that, combined with the other “conflating factors,” means that — unless summer brings regular monsoon rain — some farms may die, Greenberg said.

“It’s hard to pinpoint if and when we lose farmers and what exactly the tipping point is,” she said. “Folks are now pivoting from their plans. Maybe it means cutting back on acres, maybe not growing so much. Maybe the conversation is that this is the year when we turn in our gloves and call it good. We’ve got a lot of those conversations going on right now. The combined pressures on farming and ranching families are not alleviating. It’s possible they could force out family agriculture.”

Taking a year off generally isn’t an option, “because there are payments to be made,” said Mike Bartolo, who helped develop resilient green chile seeds over 32 years of work as a research scientist for the and serves on the board of the .

Bartolo was born and raised in the Arkansas River Valley, where water rights sell-offs to Front Range cities in the 1970s decimated farm fields and towns. Aurora and Colorado Springs officials, seeing the Colorado River Basin’s water shrinking, again are pressing for control over stressed farmers’ water rights, Bartolo said.

Planting crops now — “one of the most troubling times in agriculture I’ve witnessed in my lifetime” — means taking “a tremendous amount of risk, on top of existing risks,” he said.

“Unless there’s some miraculous turnaround, we face an era of uncertainty. We don’t know what to do. You’re kind of backed into a corner. What do you do? This is your livelihood. How do you sustain yourself? In Colorado’s rural communities, we are looking at survival.”

‘Hoping to get through this year’

State leaders say they’re committed to supporting farming and rural communities. But climate change impacts “will get worse,” Polis said, anticipating “a world of scarcity of water” where “in addition to the reduced supply, there’s also increased demand” due to population growth.

Federal immigration and foreign policies aren’t helping, he said. “If you start a war with Iran, you know that prices are going to go up a lot.”

Climate warming sets off cascading changes, such as increased pests, for which a state in Palisade breeds insect natural enemies that can be deployed to manage those pests.

But worms, mites and beetles still gnaw at the crops in Olathe, where farming has become “crisis management,” said owner David Harold, who decided last week he’ll be “cutting way back” on sweet corn.

Instead of planting corn on 1,600 acres, he’ll plant on just 100 to 300 acres. That will make it harder to find the Olathe sweet corn in supermarkets, and Harold said he’ll shift to direct sales to people who pre-order online.

Tuxedo is also “losing some workers to other areas” where migrants can work more hours, despite giving them “all the extra hours and overtime I can afford,” he said.

“We are very off balance. Fertilizer prices. Diesel prices. Transportation. I cannot get equipment in and out of here like I need to. The whole thing has been coming apart. We don’t have a clear path right now,” Harold said.

“I’m not going to put the money into these crops and then hope the bugs don’t get me, hope there’s enough water, hope there’s enough truck drivers, hope the consumer can afford it. It’s been a rollercoaster. What are we going to do? Can we take the risk? We’re struggling. Big changes are here right now. I am hoping to get through this year.”

Crop-switching and reduced planting

Along the Arkansas River east of Pueblo, farmers last week were meeting with irrigators and leaning toward a strategy of prioritizing high-value crops, such as the green chiles, while reducing corn and alfalfa.

But “it’s touch and go,” said fifth-generation farmer Rocky Musso, operator of , eight miles east of Pueblo. Musso had his fields plowed and was headed to meet with a neighbor “before we make a decision” to find out who might be able to spare unused shares of water.

“We don’t want to plant too conservatively. We will cut down to about 60% to 75% of our chile planting,” he said. “We were always taught to farm every season. You get discouraged. But it does us no good to get discouraged.”

At , established in 1890, water levels in the Bessemer Ditch were roughly 70 cubic feet per second. That’s less than half the typical spring flows during planting season, due to the low snowpack in the mountains west of Leadville above the headwaters of the Arkansas River.

The family operators produce a variety of foods, including pinto beans, onions, squash, tomatoes and pumpkins — in addition to Pueblo green chiles.

While they’re facing “the worst year in recorded history,” they made some smart moves, such as anticipating the impact of tariffs and stocking up early on fertilizers before prices went up, Jayme DiSanti said.

“We’re still going to plant. We’re going to cut back on other things and focus on vegetables,” DiSanti said. “We are not going to cut back on green chiles. That’s our thing. We’re going to be short on water. But chiles like it hot and dry. So people can probably expect hotter chile.”

WASHINGTON (AP) — Burning time for North American wildfires is going into overtime. Flames are lasting later into the night and starting earlier in the morning because human-caused climate change is extending the hotter and drier conditions that feed fires, a new study found.

Fires used to die down or even die out at night as temperatures dropped and humidity increased, but that����ap happening less often. The number of hours in North America when the weather is favorable for wildfires is 36% higher than 50 years ago, according Friday in Science Advances.

Places such as California have 550 more potential burning hours than the mid-1970s. Parts of southwestern New Mexico and central Arizona are seeing as much as 2,000 more hours a year when the weather is prone to burning fires, the highest increase seen in the study, which looked at Canada and the United States. The research looked at times when conditions were ripe for fire, but that didn’t mean fires occurred during all that time.

Recent big fires in LA and Hawaii burned at night

Fires that surge at night are tougher to fight and included the in 2023, the in 2024 and the in 2025, the study said. Maui’s at 12:22 a.m.

It����ap not just the clock that is getting extended. The calendar is too. The number of days with fire-prone weather increased by 44%, which effectively added 26 days over the past half century.

It����ap mostly from warmer, drier nighttime weather, with a bit of extra wind, the study authors said.

“Fires normally slow down during the night, or they just stop,” said study co-author Xianli Wang, a fire scientist with the Canadian Forest Service. “But under extreme fire hazard conditions, fire actually burns through the night or later into the night.”

And Wang said Earth’s warming atmosphere means it����ap like to get worse.

Tougher to fight fires at night

Fires that don’t “go to sleep” get a running start the next day, making it harder to knock them down, University of California Merced fire scientist John Abatzoglou, who wasn’t part of the study, said in an email.

“Nights aren’t what they used to be — that is, more reliable breaks for wildfire,” he added. “Widespread warming and lack of humidity is keeping fires up at night.”

Wildland firefighter Nicholai Allen, who also founded a firm that makes home fire prevention tools, said it����ap very difficult to fight fires at night.

“You have to understand that you have snakes and bears and mountain lions and all the stuff you have in daytime,” Allen said, noting a colleague was bitten by a bear. “But at night, they’re really scared and they’re running away from the fire.”

The Canadian researchers analyzed nearly 9,000 larger fires from 2017 to 2023 using a weather satellite and other tools to get hour-by-hour data on atmospheric conditions during the fires, such as humidity, temperature, wind, rain and fuel moisture levels. They created a computer model that correlated weather conditions and fire status and applied to historical data in Canada and the United States from 1975 to 2106.

Nights are warming faster than days

Scientists have long said heat-trapping gases from the burning of coal, oil and natural gas make nights warm faster than days because of increased cloud cover that absorbs and re-emits heat down to Earth at night like a blanket. Since 1975, summers in the contiguous U.S. have seen nighttime lowest temperature warm by 2.6 degrees Fahrenheit (1.4 degrees Celsius), while daytime highest temperatures have gone up 2.2 degrees Fahrenheit (1.2 degrees Celsius), according to the National Oceanic and Atmospheric Administration.

Humidity at night “doesn’t rebound” from its daytime dryness like it used to, said study lead author Kaiwei Luo, a fire science researcher at the University of Alberta.

Wildfires often coincide with drought, especially extreme drought, which means not only drier air, but hotter drier air that sucks up more moisture from the ground and plants, making fuels for fire more flammable, Wang said. In a drought, there’s often a vicious circle of drying and when it is quite dry, a warmer atmosphere has more power to suck moisture out of fuels.

Just as warmer nights especially in heat waves don’t let the body recover, the warmer nights are not allowing forests to recover, Wang said. It can take weeks for dead fuel to recover their lost moisture and be less fire-prone, he said.

“It����ap just a stress to the plants,” Wang said. “That also increases fuel load and make fire-burning more easily.”

From 2016 to 2025, wildfires in the United States on average burned an area the size of Massachusetts (28,500 square kilometers). That����ap 2.6 times the average burn area of the 1980s, according to the National Interagency Fire Center. on average for the last 10 years is 2.8 times more than during the 1980s, according to the Canadian Interagency Forest Fire Centre.

Syracuse University fire scientist Jacob Bendix, who wasn’t part of the research, called the study a sobering reminder of climate change’s role in driving “increased fire potential across almost all of the fire-prone environments of North America.”

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