Weather Alert: Flood risk in California, winter storms target east

The National Weather Service's (NWS) Weather Prediction Center (WPC) issued a warning for moderate risk of excessive rainfall in Northern California this Monday, with effects that could extend into Tuesday.

"Along the rain/snow line in Pennsylvania and the Central Appalachians, areas of rain/freezing rain will develop over the region Monday night into Tuesday. Overnight Tuesday, the rain/freezing rain will move into parts of Southern New England while snow develops over parts of Northern New England and Eastern New York State," the center explained.

In addition, according to experts, a low pressure system moving from the Northern Rockies toward the Great Lakes region, in combination with abundant moisture from the Pacific, will bring heavy and persistent rain to northern and central California.

The WPC has classified this situation with a moderate hazard (level 3 of 4), which implies a high probability of flash flooding, creek swells and possible impacts on larger rivers.

Authorities warn that areas recently affected by wildfires are especially vulnerable, as debris flows and landslides could be recorded. In addition, significant snowfall is expected in higher elevation areas, including the Sierra Nevada, Cascades, Great Basin and Northern Rocky Mountains between Monday and Tuesday.

Meanwhile, by Tuesday, the moisture system will move southward, extending precipitation into Central and Southern California.

The WPC has issued a mild risk (level 2 of 4) for excessive rainfall in both northern and central California and southern California, vigilant from Tuesday through Wednesday morning. In these areas, rains could cause localized flooding, primarily affecting urban areas, roads, small streams and fire-scarred areas.