The nations weather

AP News
Posted: Dec 20, 2011 4:34 AM
The nations weather

Weather Underground Forecast for Tuesday, December 20, 2011.

More wet and snowy weather is anticipated for the Central US on Tuesday, as a strong low pressure system continues moving eastward through the nation. This system will start the day over the Central Plains and flow around this system continues obtaining moisture from the Gulf of Mexico. This will also push cold air into the Central Plains and Rockies from the North, while warmer air will move into the East. This combination will trigger more snow showers along the back side of the system across Colorado and Kansas, while rain showers will lead the system eastward. By evening, this system will move over the Mid-Mississippi River Valley. A series of frontal boundaries will accompany this system as it moves eastward throughout the day. A cold front will extend eastward, up the Ohio River Valley, producing rain showers, with areas of snow and freezing rain along the northern side of the front. Meanwhile, another front will extend southward, moving from the Southern Plains into the Lower Mississippi River Valley. Due to ample moisture from the Gulf of Mexico, this will allow for heavy rain showers to develop, and possibly some thunderstorms with strong winds and hail.

Elsewhere, a trough of low pressure moves into the Pacific Northwest from British Columbia. This will bring more rain to Oregon and Washington, with high elevation snow developing in the Cascades. This system will move into Idaho and Montana in the evening. Temperatures in the Lower 48 states Monday have ranged from a morning low of -2 degrees at Houlton, Maine to a high of 83 degrees at Kingsville NAS, Texas