While January has been snowy as compared to normal for Denver and the Front Range, the mountains have lacked snowfall over the past couple of weeks. The last good snow in the high country being the weekend of January 12th. Meanwhile, Denver and the Front Range had a few cold fronts to drive up the above normal tally for the month.
For the season, however, snowfall is still well below normal, very similar to last year.
Even sections of the mountains are in need of snow. Here is the basin information showing percentage of normal snow/water.
Strong jet stream to bring heavy snow to the state, mostly in the mountains
Starting Thursday, a very strong jet stream will be streaking over the state and will continue through the weekend. This will push lots of moisture up against the western slope creating very heavy snowfall for those mountain ranges along and west of the Divide. All computer models agree that one to three feet will be possible, with those highest totals being in the Gunnison Basin toward the Upper Colorado Headwaters. Below is the GFS representation of that snowfall through Sunday morning.
You'll notice that there's not much snowfall over the northern Front Range, with only a small band of snowfall on top of the Palmer Ridge extending out into Nebraska. Compare that American model to its Canadian counterpart:
You can see that heavy mountain snowfall is represented rather equally; however, the band of heavy snowfall has shifted well to the north and away from the Denver area. This is where the Front Range forecast headache begins throbbing. When these systems bring in a westerly flow, it is easy to paint heavy snow on the mountains, but that westerly flow is downsloping for the Front Range, and downslope keeps the areal snowfall coverage/amounts down.
Rather than widespread snowfall, small bands of heavy snow are more likely with this setup. With strong jet stream flows, we know there will be a band of heavy snowfall somewhere from Colorado Springs to Cheyenne. The crapshoot is typically: where? The last system in Colorado developed its heavy band over Fort Collins and Larimer County. Sadly, there is no reasoning behind trying to compare that system to the one coming in -- they are too different.
As a third option, the slightly more reliable (this season and last) European model does favor a similar, to the Canadian, snow banding event over Larimer County toward Cheyenne. Although, doesn't completely keep the Denver area dry as the Canadian -- there's at least some snow for all of us in the metro areas.
How to plan
Knowing the mountains will get pounded, there will be less moisture riding over the Divide toward the Front Range. A broad-brushed light-to-moderate snowfall event will cover the entire northern Front Range. As this is a warm Pacific system, we may actually start as a rain and rain/snow mix at lower elevations before turning to snow. There will be a snow band, or two, that develop over a couple of counties that will be a moderate-to-heavy snowfall event. Right now, two of the three big players agree on a more northern setting for that, over the Cheyenne Ridge. However, don't discount the GFS yet.
Model runs Wednesday will begin to merge on a greater consensus, painting a more accurate representation of where the snow band(s) will setup.
Skiers, REJOICE, there IS heavy snowfall to hit the mountains through the weekend! Denverites. . . we'll keep you posted.