, Issued at 1201 AM PDT Wed Aug 19 2026 (Today and tonight)
A slightly more shallow marine layer tonight resulted in a somewhat later onset of stratus pushing inland with less extensive coverage than what was seen last night into early Tuesday morning. Another mild overnight into early this morning should result in stratus retreating back to the coast an hour or two sooner than we generally see this time of year. Todays warmup will barely be noticeable for areas below 1000ft away from the coast, with temperatures at higher elevations across the East Bay Hills and Santa Lucias including Big Sur and the Timber fire, running 10 degrees or more above normal. MinRH values will be in the teens this afternoon across those elevated locations, fortunately light winds continue to be a mitigating factor. The weak fetch of offshore flow above the marine layer over the southern Central Coast will shift late tonight with improved RH recovery expected into early Thursday, along with an increase in the marine layer depth.
..issued at 1201 AM PDT Wed Aug 19 2026 (Thursday through Tuesday)
Troughing persists through the extended forecast with gradually cooling setting in on Thursday and continuing through the weekend into next week. The persistent ridging to our east increases to near 600dm by the middle of next week, while continuing steer at least a couple of tropical waves around its perimeter well to our south. The potential tropical system still depicted beyond the official forecast period still appears to offer little impact for our area while we will continue to monitor any mid-level moisture advection.
(12z TAFS) Issued at 440 AM PDT Wed Aug 19 2026
Mix of IFR-LIFR conditions across the board with only LVK staying VFR. Stratus remains in place through late this morning before clearing during the afternoon/evening. Moderate confidence on timing of stratus return tonight with the marine layer remaining compressed around 1000 ft. Used a mix of persistence and ensemble guidance for the TAFs with stratus roughly arriving around 06-09Z across the interior and 00-03Z along the coast. With the marine layer compressing, it is questionable if SJC and LVK will see a return of stratus tonight but chances start to increase after 09Z. Diurnally breezy onshore winds return this afternoon and evening before weakening overnight.
Vicinity of SFO, IFR conditions prevail through late morning before gradually improving to VFR by the early afternoon. Breezy onshore winds expected during the afternoon/evening with gusts peaking between 20 to 25 knots. Low to moderate confidence in stratus return tonight with some models suggesting stratus stays confined over OAK and does not fill in towards SFO over the bay. Opted for stratus returning around 07Z tonight due to persistence and lamp guidance but this will need to be watched closely.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, LIFR conditions continue through late morning when stratus gradually starts to rise and VFR briefly returns this afternoon/evening. Model guidance is pushing for a later return of stratus (after 03Z) but this seems unlikely, even with the marine layer compressing slightly. Kept stratus returning closer to 01Z for MRY and closer to 03Z for SNS which matches better with persistence. IFR to LIFR conditions then persist through the remainder of the TAF period.
(today through Monday) Issued at 440 AM PDT Wed Aug 19 2026
Locally strong northwesterly breezes across the northern outer waters and along the coastal jet regions will bring hazardous conditions for small craft periodically through the weekend. Breezy fresh winds are expected across the San Pablo Bay and the San Francisco Bay with locally stronger gusts possible where terrain promotes wind funneling. Rough seas in the outer waters will abate Thursday with moderate seas prevailing by Friday.
Ca, None. PZ, Small Craft Advisory from 3 PM this afternoon to 3 AM PDT Thursday for Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory from 3 PM this afternoon to 3 PM PDT Thursday for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 3 PM PDT Thursday for Pt Arena to Pt Reyes 10-60 NM.
