After a slow start, snowfall totals in Denver are slightly above average this season, and the still-growing El Niño weather pattern promises to send more winter moisture our way.
“We do lean toward above-normal snowfall during El Niño,” said David Barjenbruch, meteorologist and spokesman with the National Weather Service in Boulder. “It doesn’t mean every year will be above normal. We’ve had some below.”
One “big storm” during is typically what it takes to push Denver’s snowfall into the above-average range, Barjenbruch said.
The season got off to a slow start, with no snow accumulation in September and October. But El Niño kept gathering steam, helping to deliver 11.3 inches of snow in both November and December.
The normal Denver snow total in November is 7.5 inches, with 8.1 inches normally accumulating in the city in December, according to NWS data. The cumulative total in Denver this season is 22.6 inches, compared with a normal average of 20.8.
The NWS has been tracking and gathering data on El Niño patterns since 1950, Barjenbruch said.
A complete seasonal total of snowfall in Denver during El Niño patterns averages 64.1 inches.
Seasonal snowfall totals in Denver during La Niña, which is when the eastern Pacific is cooler, average 55.4 inches.
When the Pacific weather pattern falls into a “neutral” pattern, neither too strong or weak, the seasonal average is 56.4 inches.
In the Colorado mountains, the El Niño season, so far, has left basin snowpack totals above normal.
“The mountains have been getting plenty of snowfall,” Barjenbruch said.
In the northern mountains, the snowpack is running about 110 percent. South of Interstate 70, the snowpack is running at about 120 to 135 percent of average, Barjenbruch said.
“We’re doing pretty good up there so far,” he said.
Denver weather has been influenced by a varitey of weather patterns this season, but El Niño is setting up to dominate the start of the new year, pumping Pacific moisture into the state from the south.
“It puts the odds in our favor of seeing a couple more of those storms when we get the deeper, stronger upslope we talk about,” Barjenbruch said.
Short term, however, snow should be a no-show in Denver to close out 2015.
With only a slight chance — 10 percent — of snow in Denver overnight Wednesday, there’s no cumulative snowfall in the city’s forecast through Friday.
“There’s a little bit of snow in the air this week, nothing more than light snow in the mountains and a few flurries on the plains,” Barjenbruch said. “We’ll get more in a week or so down the road.”
This season’s El Niño, the warming of surface waters in the Pacific Ocean, and its influence on weather patterns across North America, shows no sign of fizzling out soon.
The long-term Weather Service forecast calls for measurable snow in Denver around Jan. 6 and 7.
“The potential is there,” Barjenbruch said, of possible Pacific moisture heading Denver’s way. “It should pack more of a punch.”
Kieran Nicholson: 303-954-1822, knicholson@denverpost.com or @kierannicholson
