A look at the complex storm system for Wed pm through Fri pm

03/04/25 7:45pm: Even though we are not done with this current storm system (some snow still flying in the mountains and foothills) thought I'd mention the upcoming storm system which will impact the state from 8pm Wed through 8pm Fri. Models show a very complex and disorganized large trough with several imbedded waves, possibly turning into a cut-off low by Fri.

Needless to say a very challenging forecast and uncertainty is high (and will remain high). Just look at the first image loop below showing the storm system from Wed afternoon to Sun morning (crazy flow). Here are some main points

Models show a big push of Pacific moisture coming into western CO and the mountains Wed evening. Initially a warmer air mass (so some heavy / wet snow on the front-end)

For much of the mountains, including north-central, south-central and southwest CO, on/off rounds of moderate to heavy snow from 5pm Wed through 8pm Fri (with likely a break Fri am)

Models show a cold-front moving through the mountains Thu afternoon / evening (5pm-11pm timeframe) and that will bring in some heavier snow and better accumulation (in terms of colder / lighter snow)

For the north-central mountains models show an additional 6-12" of new snow by Fri evening

Heaviest snow in the mountains will likely be from the Elks (near Aspen/CB) to the San Juans (Telluride, Silverton and maybe towards WC): 10-20" additional in those areas by Fri evening

For Den/Bou and the front-range another very tricky forecast and will all depend on how far north the short-wave tracks on Thu into Fri... ECMWF (which I'm largerly basing my forecast on), shows some snow initially from 8pm Thu to 5am Fri, best chances from Boulder north to WY border: T-3" in spots, higher amounts in foothills

Then likely a better chance for some light snow for the front-range and foothills as the last part of the storm / cut-off low moves through: 3pm Fri to 3am Sat, best chances west of I-25 and into the foothills, metro areas: maybe another T-3" in spots (up to 6" in foothills), uncertainty is high

Storm system clears out of southern CO by Sat am

Then back to a ridge of high pressure, sunny and warm for Sat and especially Sun

That is all for now, except here are a few notable snow totals at the ski areas so far based on morning reports and what is snow-stakes (tomorrow, I'll have all the totals):

Copper: 14"
Vail: 11"
Breck: 11"
A-Basin: 10"
Loveland: 10"
Aspen Mtn: 10"
Beaver Creek: 9"
Winter Park: 8"
Crested Butte: 5"

First image shows the pattern from Wed afternoon through Sun am via 500mb vorticity / wind. Second image shows the deep Pacific moisture and snow moving in at 5am Thu. Images 3 and 4 compare forecast total snowfall from now through 5am Sat from latest ECMWF and GFS, take amounts with big grain of salt, the details will surely change.