Weather across America

(NATIONAL) There is a Slight Risk of excessive rainfall over parts of Central California and into Southern California through Monday morning, heavy snow over the Cascades, Sierra Nevada Mountains, and Northern Rockies, and a Critical Fire Weather risk for parts of the Southern High Plains.

Multiple areas of upper-level energy will move over the West Coast, with a developing upper-level low beginning to move onshore over the Pacific Northwest overnight Monday into Tuesday. Along with the upper-level energy, a plume of moisture will move southward along the California Coast to Southern California by Tuesday. The moisture will produce coastal rain and higher elevation snow over the Pacific Northwest and Northern California and snow extending eastward to the Northern Rockies on Sunday.  

The rain and snow will expand into Central California on Sunday evening. The rain will be heavy at times. Therefore, the Weather Prediction Center has issued a Slight Risk of excessive rainfall over parts of Central California 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 rain and higher elevation snow will steadily move southward into parts of Southern California.  Likewise, the rain will be heavy at times over the California Coast. Similarly, the WPC has issued a Slight Risk of excessive rainfall over parts of Central into parts of Southern California from Monday into Tuesday morning. Correspondingly, the associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable.

In addition, the heavy snow will be a long-duration event over the Cascades, Sierra Nevada Mountains, and Northern Rockies. The snow will result in reduced visibility and hazardous driving conditions.

Furthermore, as the upper-level low begins to move onshore, the snow levels will drop down to sea level over parts of the Pacific Northwest and down to the surface over parts of Northern California overnight Monday into Tuesday morning.

High pressure will build in over the Mid-Atlantic on Sunday into Tuesday.  On the west side of the high, warm temperatures will encompass the Southern High Plains along with gusty wind. Therefore, the SPC has issued a Critical Risk Fire Weather threat across much of the Texas panhandle Sunday into Monday due to warm temperatures, low humidity, and increased wind (15-20mph).