Weather across America

(NATIONAL) Slight Risks of excessive rainfall over Upper Great Lakes, Mid-Atlantic, and Eastern Gulf Coast, and Marginal Risk elsewhere. 

An upper-level low over the Midwest will move slowly northeastward to the Lower Great Lakes by Tuesday. Moisture streams northward across Florida, the Mid-Atlantic into the Upper Great Lakes will move off the East Coast by Monday. The system will produce rain and showers/thunderstorms over the eastern third of the country through Monday evening. Areas over the Great Lakes, Mid-Atlantic, and Eastern Gulf Coast will develop heavy rain. 

Therefore, the Weather Prediction Center (WPC) has issued a Slight Risk of excessive rainfall over parts of three regions the Upper Great Lakes, the Mid-Atlantic, and the Eastern 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 threat of excessive rainfall continues over parts of the Upper Great Lakes and the northern Mid-Atlantic, with a Slight Risk through Tuesday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable. Rain and showers/thunderstorms will continue over parts of the Northeast and Southeast through Tuesday.

Meanwhile, moisture continues to linger over the southwest portion of the country as upper-level energy over the Pacific begins to move onshore and upper-level energy trapped under an upper-level ridge will aid in producing showers and thunderstorms over the region through Tuesday. Some of the storms may produce areas of heavy rain from Sunday into Monday. 

As a result, the WPC has targeted parts of Southern/Central California, the Great Basin, and Southwest for a Marginal Risk of excessive rainfall from Sunday into Tuesday morning. In addition, the associated heavy rain will create localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain. 

On Tuesday, as the upper-level energy moves farther inland, there will be a great lightly hood of producing heavy rain with the showers and thunderstorms. Therefore, the WPC has issued a Slight Risk of excessive rainfall over parts of the Great Basin on Tuesday. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable.