Weather across America

(NATIONAL) Heavy snow over parts of the Southern Plain, Middle Mississippi Valley and over the Northeast, a Slight Risk of excessive rainfall over parts of the Southeast into the southern Mid-Atlantic, an Enhanced Risk of severe thunderstorms over parts of the Western Gulf Coast and Lower Mississippi Valley, and a Slight Risk of severe thunderstorms over parts of the Central Gulf Coast.

Low pressure, an associated front along the Gulf Coast, moves northeastward to the Mid-Atlantic Coast by Tuesday and then moves out over the Western Atlantic. The low will pull moisture off the Gulf of Mexico, producing an area of heavy rain over parts of the Southern Appalachians and Southeast. Therefore, the WPC has issued a Slight Risk of excessive rainfall over parts of the Southern Appalachians and Southeast 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. In addition, showers and severe thunderstorms will develop over parts of the Central Gulf Coast. Therefore, the SPC has issued an Enhanced Risk of severe thunderstorms over the Western Gulf Coast/Lower Mississippi Valley through Monday morning. 

The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Furthermore, there is an increased threat of EF2-EF5 and hail two inches or greater over parts of the Western Gulf Coast/Lower Mississippi Valley into Monday morning. Moreover, a narrow strip of heavy snow will develop over parts of the Southern Plains/Middle Mississippi Valley Sunday night into Monday morning.  

On Monday, the threat of excessive rainfall continues as heavy rain develops over parts of the Southern Appalachians/southern Mid-Atlantic. Therefore, the WPC has issued a Slight Risk of excessive rainfall over parts of the Southern Appalachians/southern Mid-Atlantic from 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.  

Similarly, the threat of severe thunderstorms continues on Monday. Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Central Gulf Coast/Southeast from Monday into Tuesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. 

Additionally, as the low moves northeastward, light to moderate snow will develop over parts of the Ohio Valley. Further, heavy snow will develop overnight over parts of the Northeast, Monday into Tuesday. Meanwhile, another wave of low pressure moving along a front over the Upper Midwest will produce snow over parts of the Upper Mississippi Valley and Upper Great Lakes from Sunday into Monday. 

However, light snow will continue over the Upper Great Lakes on Tuesday. Furthermore, upper-level energy moving across the Pacific Northwest to the Northern Plains will rain and higher elevation snow over parts of the Pacific Northwest through Monday evening. As the energy moves eastward, snow develops over parts of the Northern Intermountain Region/Northern Rockies that will continue into Tuesday evening. On Tuesday, snow will develop over parts of the Northern Plains.