Rainfall in San Diego. (KSWP photo)
SAN DIEGO — San Diego County will be hit by two storms this week, bringing light rain and possible snow at lower elevations and “some of the coldest air of the season.”
According to the National Weather Service, San Diego will see the initial impacts of the first storm on Wednesday morning after a brief warm-up period on Tuesday.
A deepening cold trough over Southern California will push a cold front from the northwest to the southeast throughout the day, forecasters say. During this period, the front is expected to be accompanied by rain showers and stormy winds as it moves.
With the first storm, rain is expected to fall in the morning before intensifying at midday. During this time, snow levels are expected to fall near 5,000 to 5,500 feet. Elevations above 5,500 feet could accumulate several inches of snow, the NWS says.
This means snow may be possible in areas like Cuyamaca Peak and Palomar Mountain. A winter weather advisory has been issued for the region's northernmost mountains from 10am to 8pm on Wednesday.
Total rainfall expected west of the mountains ranges from 0.20 inch to 0.40 inch, while communities in the mountains are likely to see 0.25 to 0.4 inch. Desert areas could see about 0.10 to 0.25 inches, according to the National Weather Service.
Gusty winds moving from south to west as the front passes are also expected to sweep through the area, followed by cooler air.
High temperatures will be in the upper 30s and mid 40s in mountainous areas on Wednesday, according to the National Weather Service. Outside of the mountain areas, highs will hover around the upper 50s and lower 60s for much of the county.
This first system is expected to move through the region quickly, but forecasters say it should have good support from upper-level jets. Although there may be enough instability in the system to spark some thunderstorms, according to the NWS.
Scattered showers will likely continue behind the front into Thursday morning before brief cold and dry weather sets in. By Saturday, another cold Polar Jet will begin making its way south from Canada, bringing with it possible additional rain and snow.
“This hurricane has a large amount of cold air backed up behind it, supporting a strong northerly jet with momentum to carry it across Southern California,” forecasters said Monday. “We still have a few days to go, so determining the impact now is questionable.”
However, preliminary models from the NWS predict that this storm will bring some of the “coldest air of the season” yet, dropping snow levels to about 3,500 to 4,000 feet.
The storm's track makes moisture availability slightly lower than the first, but instability associated with the air can sustain periods of light precipitation. For lower-elevation mountain areas of San Diego County like Julian and Pine Valley, this means the storm could bring some snow showers.
According to the NWS, both storms this week are expected to bring more high surf and strong currents late Wednesday into Thursday, with gusts of up to 10 feet possible on exposed, west-facing beaches.
Looking ahead, the NWS says it doesn't expect warm weather to return anytime soon: A cold snap moving in from the Arctic looms on the horizon for the region.
“Seasonal outlook forecasts appear to have spread now, with the latest (Climate Prediction Center) monthly forecast for January indicating temperatures will likely be below normal for SoCal,” meteorologists said.
