Forecast rainfall on Monday
Forecast rainfall in Southern California on Monday. Courtesy National Weather Service

An “atmospheric river” stretching across the Pacific Ocean north of Hawaii is expected to bring strong winds and heavy rain to central and northern California starting on Sunday, with San Diego experiencing lighter precipitation on Monday.

The National Weather Service expects between 2 and 5 inches of badly needed rain in the higher elevations of Northern California with flash flooding possible.

“The strongest system is expected to move through Sunday and Sunday night with heavy rain and high snow levels,” the weather service said.

In Southern California, rainfall amounts will range from 1 to 1.5 inches in the San Bernardino and San Gabriel Mountains to under half an inch in most areas of San Diego County.

Senior Meteorologist Alexander Tardy in the weather service’s San Diego office said key elements in the developing weather pattern include the remnants of a tropical cyclone and an unusually deep low-pressure system off the Pacific Northwest.

While northern and central California will get most of the rain, he said showers will be widespread when the storm system finally arrives in San Diego County.

“Monday will be our day,” he said in a live webinar. “We will get rain and it will be widespread.”

Prior to the rain, San Diego can expect cooler weather over the weekend, with a deep marine layer and the possibility of patchy drizzle.

Chris Jennewein is Editor & Publisher of Times of San Diego.