, Issued at 144 PM PDT Mon Aug 10 2026 (This evening through Tuesday night)
Afternoon visible satellite imagery shows ample sunshine across the interior, but the persistent marine layer continues to hug the coast. Pretty interesting to see all of the small eddies forming in the coastal stratus this afternoon as well. Satellite imagery also shows heat and smoke associated with the Timber Incident along the Big Sur coast. Monterey Airport was reporting haze at various times through the day due to some drift smoke. Overall transport flow is not overly strong through Tuesday so smoke/haze will be possible around the Monterey Bay / Big Sur region.
Interesting longwave pattern across CA tonight through Tuesday. The large ridge that brought oppressive heat to CA over the weekend has been split in half by a deepening upper level trough. One upper ridge is near the Four Corners and the other is well offshore. Sandwiched in the middle is a small shortwave trough inching its way toward the CA coast. Over the next 24 hours the trough will deepen further cooling the airmass and deepening the marine layer. The cooling trend noticed across the forecast area today will continue on Tuesday. Additionally, as the trough deepens a few spokes of moisture and instability will traverse the Central Coast. For now, not enough to warrant any mention of precip, but a few high level Cu are possible. Speaking of precip, the moisture in the marine layer will be high enough for coastal drizzle.
..issued at 240 PM PDT Mon Aug 10 2026 (Wednesday through next Sunday)
For Wednesday an upstream feature gets enhanced by a jet max west of Pt Conception. This feature has peaked our interest as it will lead to a low confidence high impact scenario. Latest model guidance shows there is enough moisture and instability to at least warrant a mention of showers and thunderstorms. Pt forecast soundings shows decent instability, dry low levels, but some CIN leading to the lower confidence. Pattern recognition also brings some pause as previous fires in 1999 and 2008 had upper level disturbances off the Central Coastal. This setup is close, but not exactly like previous lightning busts. As such, decided to not issue any Fire Weather Headline, but add 15% chc of showers/thunderstorms to Monterey/San Benito Wednesday afternoon and evening. Outside of the convective threat, sensible weather trends continues. Cooler weather for Wednesday and Thursday. Night and morning clouds clearing to the coast each afternoon. Coastal drizzle has been added to the forecast.
Over the weekend a subtle warming trend develops as a low deepens near the Gulf of AK and drops south. The southward trajectory well offshore of the West Coast will also the inland Four Corners ridge to ease westward.
(06z TAFS) Issued at 935 PM PDT Mon Aug 10 2026
VFR across all terminals except Monterey Bay sites and KHAF. The marine layer will continue to gradually increase through the forecast period with increased coverage expected than what was seen last night into this morning. Local offshore eddys will complicate timing once again, especially for the Bay Area.
Vicinity of SFO, VFR with until after midnight with local offshore eddys continuing to complicate exact timing of stratus. The marine layer is expected to progress farther inland tonight. KOAK may not see MVFR/IFR ceilings until the predawn hours with KSFO potentially not being impacted despite more extensive coverage of stratus due to the eddys.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, MVFR/IFR ceilings will persist through the remainder of the overnight with a slight chance of continuing through the entire forecast period as the marine layer gradually increases through the day tomorrow with steady onshore flow, breezy at times in the afternoon.
(tonight through next Sunday) Issued at 935 PM PDT Mon Aug 10 2026
Fresh to strong northwest winds will continue to produce rough seas up to 13 feet across the northern outer waters through Thursday. Long period southerly swell will gradually increase from 15 seconds through the middle of the week, up to 19 seconds by Friday into Saturday.
Ca, Coastal Flood Advisory until 2 AM PDT Thursday for CAZ006-506- 508-529-530.
PZ, Small Craft Advisory until 9 AM PDT Thursday for Pt Arena to Pt Reyes 10-60 NM.
