The Nation's Weather

Active weather was expected for the central part of the country Tuesday as a cold front pushes through the region.

A trough of low pressure was forecast to extend over the eastern part of the country from a low pressure system in eastern Canada. Flow around this system was to produce a cold front that would start the day over the Upper Great Lakes and extend into the Central Plains, pushing southeastward into the Ohio River Valley by evening. Expect scattered showers and thunderstorms were to develop along this front as high pressure over the Southeast pulls moisture in from the Gulf of Mexico. The front has a history of producing strong winds and large hail. The Northeast and New England were to see increasingly cloudy skies with a few sprinkles as this front approaches from the west.

High pressure over in the South was expected to allow for another day of hot and humid conditions from the Southern Plains to the Mid-Atlantic States. A heat advisory was issued for the Southern Plains as temperatures were forecast to surpass 100 degrees, while the Southeast and up the East Coast were to see highs in the 90s. This ridge was expected to also extend into the Southwest, allowing for highs to surpass 110 degrees. Afternoon shower and thunderstorm development was expected over southern Florida again Tuesday.

In the West, a low pressure system spinning of the coast of California was to push moist conditions onshore, kicking up low morning clouds along the coastal regions. Meanwhile, the Pacific Northwest would remain hot and dry with highs in the 90s. Fires were to threaten the region as hot, breezy and dry conditions were expected.

Temperatures in the Lower 48 states Monday ranged from a low of 37 degrees in Truckee, Calif., to a high of 114 degrees in Phoenix.

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