San Diego County will get about 1 inch of rain Monday and Tuesday from new Pacific storm

For the fifth time this winter, a North Pacific storm is drawing huge amounts of moisture from the subtropics, creating an atmospheric river that will drop from a half-inch to an inch of rain on most of San Diego County from late Monday night until late Tuesday afternoon, the National Weather Service said.

The system also will produce winds gusting upwards of 30 mph at the coast, potentially making driving more challenging on Interstate 5 and Interstate 8 and causing turbulence for commercial airliners using San Diego International Airport. And the storm is unstable enough to generate thunder and lightning throughout the county.

Forecasters added that it is possible that a significantly larger storm will strike Southern California on Saturday and Sunday.

The newest system will begin producing scattered showers late Monday night and intensify early Tuesday, generating varying amounts of rain across the region. The heaviest precipitation is expected to occur in North County, where Oceanside, Carlsbad, Vista and San Marcos could get 1 inch of rain.

Areas farther south — such as downtown San Diego, La Jolla, and Del Mar — are forecast to get about a half-inch to three-quarters of an inch while significantly smaller amounts are expected in and around Chula Vista, San Ysidro and Imperial Beach.

The outlier is Palomar Mountain, which could receive up to 2.5 inches of rain.

The system is too warm to produce significant snow in Southern California.

The state and county badly need more rain. State reservoirs currently hold about 78 percent of the amount of water they typically have at this time of year — up 10 percent from about a month ago,

But recent storms have made the soil saturated in many areas, which makes street flooding and erosion more likely, the weather service said.

Since the rainy season began on Oct. 1, San Diego International Airport has recorded 4.37 inches of precipitation, which is 0.92 inches above average. Ramona has recorded 7.0 inches, which is 2.39 inches above normal.