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Forecast Discussion:
Here we go. It is storm time.
But first, Sunday (as has been so common with these storms) - we had a ridge and strong down slope winds. Longmont hit 66F while areas around Denver reached 70F.
Figure 1 shows that the front rolled in around midnight this morning. Temperatures keep dropping, overall, all day today and into Tuesday. The initially shallow cold air may create some pre-dawn freezing drizzle or freezing fog before jet dynamics and more moist & cold air flows in getting steady snow going around noon to 2pm today. Healthy snow rates continue until after midnight Tuesday AM then drier air flows in. Snow flurries are still possible on into Wednesday AM.
Figure 2 gives you a snapshot of the storm Monday evening. As discussed yesterday, the storm will feature banded snowfall features. My call is that everyone from central Denver up to Fort Collins will see 2-4 inches of snow. Southern Denver is more like 1-3 inches of snow. Estes Park should see 3-7 inches of snow. BUT where these banded features form (and that may not be easy to nail down until things get started- but Boulder, southern Larimer, and part of Weld County has been 'under the gun' in a number of model runs recently) one could see double those snow amounts; 4-8"+.
Figure 3 is the GFS take and the banded features are visible. We are under one of those bands and are getting 4-5" of snow in this run.
Figure 4 is the WPC 50th percentile accumulation idea and we are around 4-5" here.
Figure 5 is the NAM - and we are on the north side of a band here, and in the 3-4" area.
Temperatures will be shockingly cold (especially after our pleasant, if windy, weekend). Figure 6 are the temperatures Tuesday AM and Longmont is in the single digits (also in Figure 1). Figure 7 are the temperatures Wednesday AM and we are in the upper single digits (also in Figure 1). Get ready for COLD!
The longer range forecast:
There are hints of a storm at the end of the week, but it doesn't look very big. Temperatures this week will remain largely below normal. More after this storm clears!