, Issued at 225 AM PDT Thu Mar 12 2026 (Today through Saturday)
Temperatures around 15 degrees above normal are expected today as the region is on the eastern periphery of upper-level shortwave ridging across the Eastern Pacific Ocean. Fortunately the location of the ridge will maintain onshore flow which will keep things comfortable at night and temperatures from running away. The only record high in jeopardy today is SJC with a maximum temperature forecast of 81 degrees which would tie the record from 2007. A passing upper-level shortwave trough to the north will tamp down the ridge and reinforce onshore flow, pressing pause on the warming trend Friday into Saturday. Of most impact in the short term will be minor HeatRisk. To mitigate your risk: increase hydration with water, reduce time spent outdoors or stay in the shade when the Sun is strongest, and open windows at night and use fans to bring cooler air inside buildings. With roughly 50% of our population not having air conditioning, it is going to be essential that all preparations are taken to keep places of residence as temperature controlled as possible. Examples include turning your blinds upwards and closing them during the day, ensuring ceiling fan direction is counterclockwise, and keeping windows open at night to take advantage of the natural air conditioning that is onshore flow.
..issued at 225 AM PDT Thu Mar 12 2026 (Sunday through Wednesday)
Global ensemble clusters are in agreement that an anomalously high amplitude upper-level longwave ridge will begin to move into the region from the Eastern Pacific Ocean Sunday. As the aforementioned ridge encroaches our area, winds will veer to become northerly which will further warm and dry the region as the sea breeze circulation is turned off. The axis of the ridge is expected to be overhead on Tuesday, which will yield the hottest day of the forecast period, before slowly drifting into the Colorado River Valley. While beyond the official seven day forecast, there is uncertainty in the evolution of the ridge. Even with the uncertainty, global ensemble clusters illustrate that it is likely that we will be dealing with anomalously high heights through Friday of next week. We will be in record breaking territory Sunday through Wednesday not only for daily records, but monthly records too. Forecast record breaking 850 mb temperatures and 500 mb heights are leading to a 50% probability that SJC reaches 90 degrees - this would be the first time ever in the month of March. It goes without saying that this is going to be the hottest that we have been this calendar year. Impacts wise, widespread minor HeatRisk on Saturday will give way to areas of moderate HeatRisk Sunday through Wednesday. To mitigate your risk: reduce time in the Sun during the warmest part of the day, stay hydrated with water, stay in a cool place during the heat of the day, move outdoor activities to cooler times of the day, and for those without a/c, use fans to keep air moving and open windows at night.
(12z TAFS) Issued at 434 AM PDT Thu Mar 12 2026
Current Oakland sounding shows rather dry low levels of the atmosphere. This is further reflected on satellite imagery and sfc obs showing VFR conditions with mostly clear skies. Winds are light this morning and diurnally driven. Stronger onshore flow this afternoon and early this evening. VFR holds tonight, but 35-50% chc of low cigs returning early Friday AM. VFR for tafs through the pd with some haze possible at HAF.
Vicinity of SFO, VFR. Light winds then onshore push this afternoon with 10-12 kt.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, VFR.
(today through Tuesday) Issued at 434 AM PDT Thu Mar 12 2026
Strong high pressure off the California coast will maintain moderate to strong northerly breezes across the outer waters through the weekend. Winds will eventually increase near shore late Friday. The stronger winds will result in locally hazardous condition. Winds and seas ease into the next work week.
Ca, None. PZ, Small Craft Advisory until 3 AM PDT Saturday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.
