The Nation's Weather 09.01.09

By WEATHER UNDERGROUND (AP)

Cooler temperatures were projected again for the Eastern U.S., while the Northwest was forecast to see wet weather Tuesday.

A strong ridge of high pressure would remain over a majority of the country, stretching from the Plains, over the Great Lakes and Mississippi River Valley, and into the Mid-Atlantic States and Northeast. This would allow for cool and dry air to move in from Canada, bringing frost threats to the Great Lakes and Northeast as overnight lows were expected to drop into the 30s again Tuesday night. Mostly sunny skies with pleasant conditions were anticipated with daytime highs reaching into the 70s. Air quality was expected to remain a problem for most of Texas as high pressure acts to suppress pollutants near the surface. The Southern Plains would remain hot and dry with highs reaching into the 90s.

In the South, a stationary frontal boundary was to linger over the Southeast, allowing for another day of widespread scattered showers and thunderstorms as ample Gulf moisture continued to feed into the system. Wet weather was expected to pop up over Florida and southern Georgia again on Tuesday with highs remaining in the mid-80s.

Meanwhile, in the West, wet weather was expected over the Northern Rockies and into the High Plains as a low pressure system slowly tracked eastward throughout the day. The Pacific Northwest would clear up and see pleasant weather Tuesday with highs approaching 80. In California, cool conditions were expected again while onshore flow over persisted.

Temperatures in the Lower 48 states Monday ranged from a low of 28 degrees at Leota, Mich., to a high of 118 degrees at Death Valley, Calif.