Noon MDT, Thursday, March 11, 2021

Timing changes since yesterday

The onset of the storm is a little delayed compared to previous outlooks. Significant precipitation is unlikely before Friday evening. The heaviest period of snow is likely to be late Saturday into Sunday.

Key features of weekend storm

The absolute heaviest snow is likely in eastern Wyoming. Cheyenne may very well exceed 2 feet and rival its biggest snow of record (~26″).

Heavy accumulations are likely from metro Denver northward (Colorado Springs will likely be south of the heaviest snow, but should still expect some snow & wind).

Rain?

Relatively warm, moist air will be drawn in from the southern plains, and a significant portion of the precipitation on the eastern plains may fall as rain. The rain area has trended westward with time, but it still appears that precipitation will be mainly snow for the urban corridor. I would not be surprised to see a little rain in the Denver-Boulder area prior to Saturday evening.

Most likely amounts

2-3 feet southeastern Wyoming and the east slopes of the Colorado mountains & foothills north of the Colorado Springs area. I expect to see a sub-region in this area report over three feet.

20-29 inches Fort Collins, Boulder, Broomfield, and the west suburbs of Denver

16-24 inches Denver, DIA, Longmont

Do I think there can be more? Yes, I’d put that at 20% chance. Also, the same chance (20%) that there could be less than the ranges given above.