The nations weather

Weather Underground Forecast for Thursday, February 23, 2012.

Unsettled weather will continue across the northern half of the nation on Thursday. IN the East, a disturbance from the Midwest will lift northeastward through the Ohio Valley into the Northeast. The system will bring widely scattered rain showers, periods of heavy rainfall and thunderstorms from the Tennessee and Ohio Valley into the Mid-Atlantic. A mix of precipitation is expected in the Northeast Thursday through Friday. Expect periods of localized significant wet snowfall across the higher elevation and east of Lake Ontario. In addition to snow, periods of heavy rainfall are anticipated in much of New England. To the south, there will be a slight risk of severe thunderstorms ahead of an associated cold front late Thursday into Thursday night across parts of the Lower Ohio and Tennessee Valleys into the Gulf States. Isolated supercells in these regions may produce large hail, damaging wind gusts, and tornadoes.

Behind this activity, energy from the Northwest will advance into the Upper Midwest. Moisture spreading into the Plains will aid in producing rain and snow in the Northern Plains and rain showers in the Mid-Mississippi Valley and western Ohio Valley. As this system advances southeastward, expect areas of snow showers to persist over portion of the Northwest and Central Rockies.

Elsewhere, warm temperatures will remain in place from the Central and Southern Plains through the Mid-Atlantic, before the next trough of low pressure arrives Friday with cooler weather. Temperatures in the Lower 48 states Wednesday have ranged from a morning low of 6 degrees at Morris, Minn. to a high of 84 degrees at Laredo, Texas