A May snowstorm has already dumped heavy snow in parts of the Rockies from Wyoming into Colorado, not just in the high country, but also along the Front Range, including Denver and Cheyenne, and will slowly wind down Wednesday.
Where It's Snowing Now
Snow continues to fall from southeast Wyoming and the western Nebraska Panhandle into Colorado, as the radar map below shows.
Latest Snow Reports
Cheyenne, Wyoming, picked up 8.9 inches of snow, their heaviest snowfall of a paltry season, and most from any snowstorm since a mid-March 2021, according to the National Weather Service. This snow prompted a shutdown of Interstate 80 in both directions from Laramie to Cheyenne Tuesday. While still snow covered, that stretch is open this morning.
In Colorado, up to 20 inches of snow has been reported in and near Rocky Mountain National Park. Over two feet piled up in nearby Estes Park and 5.5 inches fell at Denver International Airport through Wednesday morning.
The NWS office in Boulder reported 10.7 inches of snow, their heaviest May snowstorm in 13 years.
While major interstates were mainly wet in downtown Denver, some snowy travel was reported on Interstate 25 from north of Denver to Ft. Collins.
The weight of wet snow on trees and power lines has already triggered about 56,000 outages, mainly in the Denver metro area, according to PowerOutage.com.
Forecast
Snow will gradually end from north to south across Colorado and far northern New Mexico this afternoon, ending by this evening.
The heaviest additional accumulations are expected in the foothills immediately west of Interstate 25 in central and southern Colorado, with anywhere from 6 to 12 inches of additional snow.
In Denver, a few more inches of snow is expected, with higher amounts in the southern and western suburbs.
Impacts
- Expect winter driving conditions in the high country of Colorado, including Interstate 70 from Vail eastward. In lower elevations, expect snowy stretches of Interstate 80 in southeast Wyoming. Stretches of Interstate 25 will become snow- or slush-covered in much of the state and could become challenging over the Palmer Divide from south of Denver to north of Colorado Springs. Parts of Interstate 70 east of Denver may also become slush-covered and slippery.
- The weight of this heavy, wet snow could down trees and knock out power. Some of these downed trees could block roads. Leave extra time if you're traveling in the foothills and high country Wednesday.
(MORE: Falling Trees One Of Most Underrated Weather Dangers)
How Unusual Is This May Snow?
In much of the U.S., snow is usually in the rear-view mirror once we've reached May.
But not in the Rockies.
Both Cheyenne and Denver average 1 to 3 inches of May snowfall, and measurable snowfall over nine months from September through May.
That's due to their higher elevation. You know Denver is the "Mile High City." Cheyenne, Wyoming, sits on a ridge almost 1,000 feet higher than Denver.
According to the National Weather Service, Denver's last measurable snow of the season has happened in May twice in the last 10 years, on May 21, 2022, and May 21, 2019.
Denver's record latest measurable snow was on June 2, 1951 (0.3 inches). The city also picked up 5.6 inches of snow on May 29, 1975, three days after Memorial Day.
(MORE: What's Typical In May)
Record May Snowstorm?
The bar graph below shows both the record May monthly snowfall tallies and average May snowfall for both Cheyenne and Denver. Those record tallies would resemble average monthly snowfalls in the middle of winter in other snowy places in the U.S.
Cheyenne's record May snowstorm was an 18.3-inch pummeling exactly 48 years ago, from May 5-6, 1978. Cheyenne had eight other May snowstorms with at least a foot of snow, including in mid-May 2017 (14.3 inches) and mid-May 2014 (12 inches).
Denver's record May snowstorms were each 12.4-inch events in that same May 1978 storm as Cheyenne, as well as in mid-May 1912. That record is likely safe in this storm.
Snow Deficit
The West has suffered a major snow drought this past season, with the least amount of snow in several decades in much of the Rockies and mountain West.
As the graph below shows, since mid-January, Colorado's snowpack has been at or below its record low since at least 1987.
This snowfall won't do much for that long-term drought built up over months.
But it is providing some fresh snow for the few ski areas still open, including Copper Mountain and Arapahoe Basin.
Prior to this storm, Cheyenne, Wyoming, had picked up only 17.5 inches of snow since fall.
That may sound like a lot of snow for, say, Nashville or Oklahoma City.
But in Wyoming's capital city, that's almost 43 inches below their seasonal average through May 4.
And it's the second least amount of snow to date for any snow season in records dating to the 1880s, behind only the 1965-66 season (11.1 inches).
The last time they picked up even just an inch of snowfall was three days before St. Patrick's Day.
Jonathan Erdman is a senior meteorologist at weather.com and has been covering national and international weather since 1996. Extreme and bizarre weather are his favorite topics. Reach out to him on Bluesky, X (formerly Twitter) and Facebook.
