2 STORMS EXPECTED TO HIT SAN DIEGO COUNTY TODAY, TUESDAY

Weak system to be followed by larger storm, strong winds

The spring equinox arrives today. But it will feel like midwinter across San Diego County. A weak storm will deliver light rain ahead of a bigger system that will push ashore Tuesday with heavy precipitation, moderate snow, biting cold and fierce winds from the desert to the sea, the National Weather Service said.

Forecasters said the storms could raise the water level in the San Diego River in Mission Valley to nearcliff flood stage and produce winds strong enough to snap trees from Oceanside to San Ysidro, where gusts will be in the 54 to 60 mph range.

The coast and inland valleys are projected to receive up to 3 inches of rain from early Tuesday to early Thursday and 4 to 5 inches at Palomar Mountain, which has recorded 49.77 inches of precipitation since the rainy season began on October 1. That’s 19.36 inches above average.

The heavy rain is worrisome to public works crews. The landscape is saturated from a seemingly endless string of Pacific storms, many of them beefed up by moisture from the subtropics. The rain contributed to a collapse at Black’s Beach in January and created a massive sinkhole on state Route 78 in Oceanside last week.

The larger storm now approaching San Diego has tapped into moisture from northwest of Hawaii, generating an atmospheric river that is forecast to move directly over San Diego County.

The incoming winds also have people on edge. The weather service said in an advisory that the system could “translate to a very strong wind event that we only see once every few years. The strongest winds will be ahead of and with the cold frontal passage on Tuesday.”

The air will become very unstable late Tuesday and early Wednesday and could result in sporadic thunder and lightning across much of the region.

On Wednesday, the conversation will shift to the cold air. The daytime high in San Diego is expected to reach 59, which is eight degrees below average. Communities across the region will be 5 to 15 degrees cooler than normal.

The cold air also will lower the snow level. It’s expected to drop to about 4,000 feet on Tuesday night. Forecasters said that Palomar Mountain will receive 8 to 12 inches of snow while Mount Laguna gets 3 to 4 inches.