Weather Underground Forecast for Friday, March 23, 2012. Severe weather will persist over the Eastern Valleys on Friday as a low pressure system continues moving eastward from the Plains. Flow around this system pulls more warm and moist air in from the Gulf of Mexico, while also pushing a cold front eastward. Expect moderate to heavy showers and thunderstorms to develop along and ahead of this front as it stretches from the Great Lakes and Ohio River Valley, into the Gulf of Mexico. Rainfall totals will range from 3 to 4 inches along the southern side of this system, while the Midwest and Ohio River Valley will see lighter and more widespread showers. Flooding will remain of concern for these areas as this system has brought heavy rains to the Southeast for the past few days. In areas of severe thunderstorm development, expect large hail, strong and damaging winds, and possibly a few tornadoes. Also, as the cold front passes, temperatures will finally subside across the Eastern US. However, high temperatures will remain warm, ranging in the 70s in the Ohio River Valley, parts of the Northeast, as well as the Mid-Atlantic states. Meanwhile out West, a trough of low pressure continues moving through the Northwestern quadrant of the nation. This will kick up a few more light snow showers over the Northern Rockies as it quickly advances northeastward into Central Canada. Snowfall accumulations will remain light with 1 to 2 inches likely. Temperatures in the Lower 48 states Thursday have ranged from a morning low of 15 degrees at Gunnison, Colo. to a high of 89 degrees at Plant City, Fla.