The Nation's Weather 09.28.09

By WEATHER UNDERGROUND (AP)

Monday's main weather event was forecast to develop in the Midwest as a deepening area of low pressure in the northern Great Lakes swung a cold front through the Upper Great Lakes.

Significant precipitation with scattered thunderstorms and brief periods of strong winds were expected to develop in advance of the system throughout the day. Gusty west to southwesterly winds of up to 45 mph would continue to affect the Great Lakes and the Ohio Valley as the front trekked eastward into the Northeast during the latter half of the day. In the wake of this system, cooler temperatures were expected throughout the Midwest.

Cool weather was also expected in the West as low pressure returned to the West Coast on Monday. An approaching trough of low pressure would increase onshore flow across California and the Pacific Northwest, dropping daytime temperatures to at or below seasonal averages. Moist onshore flow may also trigger a few scattered showers along the Pacific Northwest Coast, forecasters said.

Elsewhere, warm and quiet weather was expected throughout the majority of the Southeast.

Temperatures in the Lower 48 states Sunday ranged from a low of 24 degrees at Stanley, Idaho, to a high of 112 degrees at Death Valley, Calif.