Weather across America

(NATIONAL) A Slight Risk of severe storms from the Northeast to the Mid-Atlantic, a Slight Risk of excessive rainfall over parts of the Central Gulf Coast, Tennessee Valley, and the Southeast, and snow over portions of the Northern/Central Rockies. 

A front extending from the Northeast to the Central/Western Gulf Coast will move eastward off the Northeast and Mid-Atlantic Coast by Monday. Showers and thunderstorms will develop along and ahead of the boundary through Monday. In addition, the front and moisture pooling along the boundary will destabilize the atmosphere. Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Northeast to the Mid-Atlantic through Monday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes.

In addition, heavy rain develops along the boundary from the Northeast to the Central Gulf Coast. Therefore, the WPC has issued a Marginal Risk of excessive rainfall with these thunderstorms from the Northeast to the Central Gulf Coast through Monday morning. The associated heavy rain will create localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain. However, the WPC has also issued a Slight Risk of excessive rainfall over portions of the Central Gulf Coast through Monday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable.

On Monday, the front lingers over the southern Mid-Atlantic, extending westward to the Central Gulf Coast and Southern Rockies. Showers and thunderstorms will continue over the Mid-Atlantic to the Southeast/Central Gulf Coast. There will also be a Marginal Risk of severe thunderstorms over the southern Mid-Atlantic and the Southeast on Monday into Tuesday morning. 

Upper-level energy moving across the Southeast will trigger heavy rain on Monday. Therefore, the WPC has issued a Slight Risk of excessive rainfall with these thunderstorms over Central Gulf Coast, Southeast, and Southern Appalachians on Monday into Tuesday morning. 

Additionally, moisture will surge northward over the Southern Plains into the Central Plains as upper-level impulses will move across the region on Monday to trigger showers and thunderstorms. Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Southern Plains from Monday through Tuesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes.

The energy will also produce areas of heavy rain on Monday. Therefore, the WPC has issued a Slight Risk of excessive rainfall with these thunderstorms over south-central Texas and a second area over central Kansas into Oklahoma and parts of the Texas Panhandle on Monday into Tuesday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable.

On Tuesday, a wave of low pressure over the western end of the front will move from the Southern Rockies into the Southern Plains. The system will produce showers and thunderstorms over parts of the Southern Plains. Therefore, the SPC issued a Slight Risk of severe thunderstorms over parts of the Southern Plains on Tuesday. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. The storms will also produce heavy rain over the region. Therefore, the WPC has issued a Slight Risk of excessive rainfall over parts of the Southern/Central Plains and the Middle/Lower Mississippi Valley on Tuesday. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable.

Meanwhile, upper-level energy will aid in developing rain with embedded thunderstorms and higher elevation snow over parts of the Northern/Central Rockies on Sunday evening into Monday morning. 

Monday, rain will develop over parts of the Northern/Central Plains. Overnight Monday, rain and higher elevation snow will return to parts of the Northern/Central Rockies, with rain continuing over the Northern/Central Plains. The rain will expand into parts of the Middle Mississippi Valley on Tuesday.

A front will also move onshore over the Pacific Northwest Monday, moving inland to the Northern High Plains/Northern Rockies by Tuesday. Light rain will develop over parts of the Pacific Northwest, with pockets of snow developing over the highest elevations overnight Monday. The rain ends over the Pacific Northwest by Tuesday morning. Rain will continue over parts of the Northern Intermountain Region on Tuesday.

Elsewhere, there are two areas of Critical Fire Weather Risk over parts of the Southwest, Southern Rockies, and the Great Basin on Sunday into Monday morning. The fire weather threat lessens on Monday with an Elevated Risk over parts of the Southwest and Southern Rockies.