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Updated: 9:00 AM GMT on March 18, 2010

Weather Summary

Weather Underground Forecast for Thursday, March 18, 2010.

After a brief period of fairly quiet weather activity over most of the West, a new patch of active weather will move into region on Thursday. A strong Pacific storm system over southwestern Canada will produce a mix of precipitation across the Northern and Central Rockies and High Plains as it drops southeastward into Wyoming on Thursday. The brunt of this precipitation will fall to the north of an associated frontal boundary that will stretch across the Central Great Basin and into the Central Plains. Periods of light, scattered rain showers are expected from areas of southern Nevada through southern South Dakota and northern Nebraska with snow blanketing the higher elevations. Rainfall across these regions will quickly change into snow by the afternoon as cold air from Canada sinks southward and drops temperatures to below freezing. The heaviest amounts of snow are expected throughout Wyoming on Thursday and will spread southward into Colorado on Friday. Meanwhile, gusty north winds will accompany wet weather and will create periods of blowing and drifting snow throughout the day.

The remainder of the West will continue to see dry and warm weather conditions due to lingering high pressure.

In the East, the precipitation event across the Southeast will taper down as the low pressures system affecting the region moves into the Atlantic. Areas of scattered showers are expected to persist from the eastern Gulf coast to the southeastern coast. Meanwhile, high pressure will dominate the rest of the East with mostly dry conditions and unseasonably mild daytime temperatures from the Great Lakes through New England.

Temperatures in the Lower 48 states Wednesday ranged from a low of 11 degrees at Lake Yellowstone, Wyo. to a high of 91 degrees at Santa Ana, Calif.