The Nation's Weather 12.03.09

By WEATHER UNDERGROUND (AP)

A strong storm in the Southeast was forecast to produce more active weather as it moved northeast on Thursday.

Healthy moist flow from the Gulf of Mexico and Atlantic Ocean was expected to wrap around the system and fuel another round of light to moderate precipitation in the Mid-Atlantic, the Ohio Valley and the Northeast.

As the system moved toward southeastern Canada, energy from the storm was expected to spread across the Upper Midwest and leave snow in some areas.

The tail of a cold front associated with this system was forecast to spark rain and thunderstorms in southern Florida as the front exited into the Atlantic Ocean.

Chilly and less active weather was expected to persist behind this system in the Central U.S. as a frigid ridge of high pressure dropped into the region.

Cold air flow associated with the system was expected to push temperatures below seasonal averages from the Rockies through the Plains.

High pressure could keep dry and quiet weather in place throughout the West.

On Wednesday, temperatures in the Lower 48 states ranged from a low of -16 degrees at Yellowstone, Wyo. to a high of 90 degrees at Boca Raton, Fla.