A low pressure system is expected to bring showers and a slight chance of thunderstorms to San Diego County starting Thursday.
Fair and warm conditions are expected in San Diego County for most of the day, but a slight chance of showers is in the forecast overnight and rain will be likely Friday morning and afternoon, according to the National Weather Service. Forecasters said the chance for measurable precipitation would jump from 20 to 70 percent by Friday.
A shortwave low pressure trough is expected to cause downpours north of San Diego County, but the lighter precipitation will fall south and east of Los Angeles, according to the weather service.
"Favorable orographic flow could wring out over an inch of rain in the San Gabriel and San Bernardino Mountains, but far lesser amounts are expected in the lowlands, especially as you head south into San Diego County," according to the weather service.
Predicted rainfall amounts Thursday night through Friday were .01 of an inch of rain in coastal San Diego; .02 in the Miramar area; .03 in Alpine, Borrego Springs and Ramona; .05 on Mt. Laguna; .06 in Oceanside; .08 in Escondido; .11 in Julian; and .37 on Palomar Mountain, according to the National Weather Service.
The low pressure system is expected to move out of the region Friday, but a few showers may be possible in the mountains on Saturday. A second low pressure trough is expected to bring more rain Sunday, and a third will hit San Diego County Tuesday.
