A slow-moving surface low associated with a deep midlevel trough caused widespread 1 to 3 feet of snowfall in Colorado this weekend. There were isolated reports of up to 4 1/2 feet of snow from the storm. To the east, 1 to 3 inches of rain fell in the western and central Plains this weekend, and 2 to 5 inches of rain occurred along and near the northwestern Gulf Coast. Seasonably cool air caused up to 1/2 foot of snow to fall in northeastern Minnesota yesterday. In the West, strong broad midlevel ridging allowed quiet, warm weather to pervade the region, with highs in the 70s at lower elevations in the northern West.
Much of the lower-elevation snowpack has melted in the West, and the higher-elevation snowpack is quite warm through the Northern Rockies and West Coast states, as well as at middle elevations in the Great Basin and parts of the Central Rockies. The remaining snowpack across the northern U.S. continued to melt, that is, where new snow wasn't falling.
The system which brought he rain and snow to the central and southern U.S. will shift northeastward during the next few days. Around an inch of rainfall is likely along the central East Coast today, and up to 3 inches of rain is expected along at least coastal Maine tomorrow. Farther west, the air will be sufficiently cold at the surface beneath a midlevel disturbance to cause up to a foot of lake-effect snowfall south of Lake Superior today.
The broad upper-level ridging over the West will shift eastward during the week and bring above-normal air temperatures to the Plains, Midwest, and Great Lakes during the week. The snow which remains (and the new snowfall expected through tomorrow) will rapidly warm and melt under quiet, clear skies.