12:30 PM MDT, Sunday, April 18, 2021
A strong cold front on Monday will put an end to our brief warm-up, and snow will likely develop Monday afternoon and continue into the evening. The cold front will likely be through Cheyenne by morning. Farther south along the Colorado Front Range, the morning may start mild, but the day will turn colder. A roughly 12-hour period of snow (maybe a little rain at the start in the lower elevations) is likely to develop in the afternoon, early-to-mid afternoon in southeastern Wyoming, late afternoon farther south in metro Denver. There will probably be about 1-4 hours of heavy snow from some east-west oriented bands that move north-to-south. Snow should be over by Tuesday morning, but temperatures by Tuesday morning are likely to be the coldest of the month, teens to around 20 in the urban corridor.
Accumulation below 6500 feet: mainly 3-6″. Being close to the foothills is not necessarily where the highest amounts will be. It’s more dependent on where the east-west bands are at their peak strength.
Accumulation above 6500 feet: 5-10 inches, again this is somewhat dependent on where the bands of heavy snow set up.
I’d like to say that this long duration cool spell will end, and I expect that it will end by the weekend. But another weak storm at midweek is likely to bring some more precipitation and extend the colder-than-average stretch into Thursday.