, Issued at 218 PM PDT Wed Aug 12 2026 (This evening through Thursday night)
Isolated thunderstorm potential continues through this evening along the Central Coast with increasing confidence compared to this morning. Radar shows a line of storms developing off of the Big Sur coastline and moving in to Monterey County. As of this morning/early afternoon, we have cells moving inland in the vicinity of the Timber Fire which produced lightning both offshore and on land. This cell backbuilt to the southwest with additional cells developing in the wake of the original (inland) cell over the marine environment. These additional storms have been slowly moving inland in the vicnity of the Timber Fire and may also become favorable to produce lightning. Any of these cells will be capable of producing gusty, erratic wind and dry lightning with any rain evaporating before reaching the surface due to the elevated storm nature. Fuels are incredibly dry right now with near critical fire weather concerns across Monterey and San Benito Counties. If dry lightning occurs, it is likely to result in additional fire starts. Residents of interior Monterey and San Benito County (particularly along and within the higher terrain) should stay weather aware, avoid unnecessary activities that may result in sparks/fire, and follow guidance from local officials. Confidence is highest in thunderstorms over the elevated terrain with orographic lift acting as the trigger for storms to develop. This is an ongoing event and we will be paying close attention to the radar this afternoon and evening as it evolves.
Tonight into tomorrow, a low pressure system offshore will move into the Central Coast and bring additional chances for thunderstorms through Thursday morning. HRRR guidance shows several hundred joules/kg of MUCAPE moving across the Central Coast tonight into early Thursday with decent upper level support (700-500 mb lapse rates between 7-8 C/km) and lingering monsoonal moisture. Given that storms are currently occurring along Big Sur, it is likely that we will see additional storms again tonight through tomorrow morning across the Central Coast. Storms tonight and tomorrow morning could potentially reach as far north as the Santa Cruz Mountains and the South Bay. Storms are most likely to form along the higher terrain and be driven by orographic lift.
..issued at 218 PM PDT Wed Aug 12 2026 (Friday through next Tuesday)
Thunderstorm chances diminish after Thursday with drier conditions to prevail into next week. Temperatures will remain well below normal across the Bay Area and Central Coast as upper level troughing persists through this weekend. This will keep highs in the 60s closer to the shoreline and in the 70s to mid 80s across the interior. The exception will be the interior Central Coast where highs will warm into the upper 80s to low 90s late weekend into early next week. Temperatures gradually warm next week as ridging pushes into the Desert Southwest from the Central US and troughing continues over the Eastern Pacific Ocean.
(06z TAFS) Issued at 919 PM PDT Wed Aug 12 2026
Currently VFR for majority of terminals with KHAF and Monterey Bay sites in MVFR/IFR. Deeper marine layer (1800ft to 2000ft) and stronger onshore flow will result in more widespread stratus intrusion while an offshore eddy will continue to complicate timing of MVFR/IFR ceilings for the Bay Area, especially KSFO. A quasi- stationary upper level low and associated trough at our latitude will produce gusty onshore flow at times through the TAF period.
Vicinity of SFO, Gusty onshore flow will persist through much of the TAF period with a better inland push overnight than we've seen the past week. However, as a mentioned above, an offshore eddy will continue to complicate timing and coverage of MVFR/IFR ceilings, especially at KSFO.
SFO Bridge Approach, Expect MVFR/IFR ceilings in vicinity of KSFO even if not measured at the terminal.
Monterey Bay Terminals, Quasi-stationary upper level low will eventually produce and maintain IFR/LIFR ceilings overnight through at least late morning, and possibly into the afternoon especially at KMRY. A slight chance, but low confidence of KMRY remaining socked in through the forecast period.
(tonight through next Tuesday) Issued at 919 PM PDT Wed Aug 12 2026
Fresh to strong northwest winds with isolated gale force gusts will ease by early Thursday morning, with rough seas becoming moderate by Thursday evening. Long period southerly swell will gradually increase Thursday reaching 16 to 18 seconds (possibly higher at times) by Friday and continuing through the remainder of the weekend. Visibility may decrease due to haze and smoke nearby the Big Sur coastline due to the Timber fire.
Ca, Coastal Flood Advisory until 2 AM PDT Thursday for CAZ006-506- 508-529-530.
PZ, Small Craft Advisory until 3 PM PDT Thursday for Pt Arena to Pt Reyes 10-60 NM.
