San Jose rolled in today under a gray sky and about 57°F, with patchy fog hanging over low-lying neighborhoods until the marine layer loosened its grip. Inland spots are still on track to warm up fast, with highs near 76°F expected this afternoon under mostly sunny skies. A slow-moving Pacific low is waiting in the wings and will bump up the odds of showers and thunderstorms later tonight and through the weekend, with the strongest thunder chances lining up for tomorrow and Saturday.
Foggy Start, Warm Finish
Areas of fog are most likely before 9 AM and should mix out by late morning, giving inland neighborhoods a decent shot at upper-70s by mid-afternoon, while cooler bayfront areas stay milder. South-southwest breezes look light to moderate, generally 1-9 mph, with the usual extra gusts on exposed ridgelines and bridges. Morning commuters will want to watch for pockets of reduced visibility in the thicker fog patches.
Thunderstorms Tonight Through The Weekend
A chance of rain creeps in tonight, with a window of light rain or showers between about 8 PM and 2 AM, then more numerous showers and thunderstorms tomorrow and Saturday. The National Weather Service is calling for pockets of locally heavy rain, roughly 0.5-1.5 inches across much of the area and up to 3 inches in favored coastal ranges, and warns that storms could bring lightning, small hail, and erratic gusts, NWS San Francisco. Forecasters add that Saturday's system may have enough low-level spin to support isolated rotating storms, which bumps up the risk of severe gusts in the strongest cells. Mariners and small-craft operators should be ready for sudden squalls and rough, hazardous seas as the storms roll through this weekend.
What This Means For Your Plans
Morning errands look fine once the fog lifts, but if your plans are outside tomorrow or Saturday, build in a backup and stay away from open areas during lightning. Brief heavy downpours can trigger localized street flooding in low-lying or poorly drained areas, so ease up on the gas near standing water and pad your commute time. If you work outside or run events, keep an eye on the sky, be ready to pause activities and let the more intense cells pass.
Expect a sunny, warm afternoon today, then a turn to unsettled weather starting tonight and running through Sunday, with the most disruptive thunderstorm chances lining up for Friday and Saturday. Keep an umbrella handy, allow extra time for travel and stay tuned to the National Weather Service for any watches or warnings as conditions evolve.
