The Nation's Weather

Severe weather was expected to sweep through the Plains and Great Lakes on Tuesday as a low pressure system lingered in eastern Canada.

A strong and slow-moving low pressure system moving eastward through Canada was likely to produce a cold front that would start the day over the Central Plains and push southward toward the Southern Plains and reach into the Mid-Mississippi River Valley. Meanwhile, high pressure in the Mid-Atlantic was expected to create a strong northward flow from the Gulf of Mexico, feeding abundant moisture into this system. Forecasters expected periods of heavy rainfall, strong winds, and even tornado development. Most places were expected to see less than a quarter of an inch of rain, while up to an inch or two was likely to fall in areas of thunderstorm development.

In the East, a frontal boundary was expected to linger over the East Coast and allow for scattered showers to persist on Tuesday. A weak ridge of high pressure was forecast to build in over the Ohio River Valley, allowing for mostly sunny skies and highs in the 80s, before the front approaches from the Central US.

In the West, forecasters expected another day of hot temperatures with sunny skies as a strong ridge of high pressure remained over the West Coast. Heat advisories were expected to remain in effect for the Southwest due to temperatures expected to riseabove 110 degrees again on Thursday, while the Pacific Northwest will see another day in the 90s.

Temperatures in the Lower 48 states Monday ranged from a low of 36 degrees at Leadville, Colo to a high of 117 degrees at Needles, Calif.

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On the Net:

Weather Underground: http://www.wunderground.com

National Weather Service: http://iwin.nws.noaa.gov

Intellicast: http://www.intellicast.com

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