A pair of Pacific low pressure systems will merge off the British Columbia coast Wednesday before moving southward toward San Diego County, forecasters said.
The merged systems will form a cold Pacific storm that should arrive in the county late Thursday night, bringing rain, snow and wind gusts up to 65 miles per hour through early Saturday, according to the National Weather Service.
"There are still some minor model timing differences but overall it is expected to be much cooler during this period with strong gusty winds in the mountains and deserts, with showers along and west of the mountains and in the upper deserts, and with snow levels lowering to around 2,500 feet," an NWS advisory said.
Rainfall totals from the storm are expected to range from up to a quarter-inch near the coast to around a half-inch in the mountains. Also in the mountains, three to six inches of snow is expected above 4,000 feet, with local amounts of six to nine inches mainly above 6,000 feet.
The weather service said a couple of inches of snow is possible in the far inland valleys near the coastal foothills late Friday night and early Saturday.
Isolated thunderstorms are also possible Friday night, with small hail, according to the NWS.
"This weather could be deadly for unprepared campers or hikers," a weather service advisory said. "The combination of strong winds, low visibilities and snowfall could create hazardous travel conditions in the mountains, especially Friday and Friday night."
-City News Service