Weather Underground Forecast for Sunday, April 21, 2013.
Another winter storm develops over the Northern Rockies and Northern Plans on Sunday as a trough of low pressure moves eastward through the region. this system will create a cold front that advances eastward over the Northern Plains and into the Upper Midwest. On Sunday, areas of heaviest precipitation will remain over the NOrhtern Rockies, while some light and scattered showers will move into the Upper Midwest. Expect snowfall total over the Northern Rockies to range from 2 to 6 inches, with another 5 to 10 inches likely at higher elevations through Sunday evening. The Upper Midwest will see 1 to 2 inches of snow, mixed with rain in the warmer hours of the middle of the day and afternoon. This system will have less moisture associated with it than the previous late-season winter storms, but will bring another round of cool air to the Northern Plains and Upper Midwest. A cold front extending over the Central Plains will allow for showers and thunderstorms to develop. There is a slight chance that these storms will turn severe with strong winds and hail.
Meanwhile in the East, a ridge of high pressure will maintain dry but cool conditions across the Eastern Valleys and East Coast. The tail end of a cold front lingers over Florida and kicks up more scattered showers and thunderstorms throughout the day. While this front will continue to weaken, there remains a chance of severe thunderstorms with large hail and damaging wind gusts.
Temperatures in the Lower 48 states Saturday have ranged from a morning low of -9 degrees at Crane Lake, Minn. to a high of 91 degrees at Marathon, Fla.