Weather Underground Forecast for Monday, December 26, 2011.
Active weather will continue in the southeastern quadrant of the nation on Monday as a frontal system in the northern Gulf of Mexico begins to shift eastward. Low pressure along this system will lift northeastward across the central Gulf Coast toward the Tennessee Valley with a rich plume of moisture from the Gulf of Mexico. This will lead to steady rain showers with periods of heavy rainfall and thunderstorms from parts of eastern Texas and eastern Oklahoma through western Tennessee and Alabama. Areas experiencing heavy rainfall should expect totals of 2 to 3 inches by Monday night. Heavy rainfall near the southern Mississippi River combined with yesterday¼'s totals will increase chances of local flooding and flash flooding through the day.
To the north, a strong disturbance passing through the Lower Great Lakes and Northeast late Sunday night through early Monday morning will kick up lake-effect snow showers downwind of the Lower Great Lakes and snow showers in the Northeast. This activity will wind down during the morning as high pressure follows quickly behind this system. Expect generally dry conditions in the Ohio Valley, Great Lakes, Northeast, and Mid-Atlantic during the day.
In the West, precipitation in the Pacific Northwest will spread eastward into northern Idaho overnight leaving behind a couple of inches of snow Monday morning. The next front in a series of a disturbances this week will move across the Pacific Northwest Monday evening with periods of moderate to locally heavy coastal rain, breezy to locally windy conditions, and mountain snow. Temperatures in the Lower 48 states Sunday have ranged from a morning low of -13 degrees at West Yellowstone, Mont. to a high of 85 degrees at Tampa Macdill AFB, Fla.