, Issued at 236 AM PDT Tue Oct 14 2025 (Today and tonight)
All signs point to rain shower/thunderstorm activity declining through the day as the surface low pressure system and it's attendant cold front (as well as it's mid-to-upper level support) will weaken and exit the region through the day. There will still be chances for rain showers and thunderstorms until the features exit around midnight. Let's take a deep dive into the thunderstorm potential for today by addressing the critical ingredients of lift, instability, and moisture. In addition to what has already been discussed lift wise, a 95 knot jet streak from a dive in the Polar Jet Stream will shift into our region today, which could allow for more ascent. Instability will be characterized by low CAPE (500 Joules/kilogram) and conditionally unstable lapse rates (7 degrees Celsius/kilometer). Moisture will ebb and flow throughout the day and will be highly dependent upon the placement of the surface low pressure system. A solution over the water will be more moist than a solution inland which will be capable of entraining drier air into the system. With similar ingredients on tap for today as what was present yesterday, I would be very surprised if today outperformed yesterday given the very limited amount of lightning that was observed. The best chances for thunderstorms (up to 15%) are for Southern Monterey and San Benito Counties and the adjacent waters. Thunderstorm or not, cells will still be capable of producing locally heavy rainfall resulting in nuisance/urban flooding, erratic/gusty winds, small hail, and waterspouts. Caution should continue to be exercised through the day when driving. Roads will still be wet for this morning's commute so please allow extra patience, space, and time when driving, especially for super commuters who will undoubtedly be driving in the dark. Remember: turn around, don't drown! This system is also a cold one. Calm, clear, and cold conditions tonight will yield near-freezing temperatures for far interior Monterey and San Benito Counties east of Highway 101. In addition to the aforementioned near-freezing temperatures, patchy frost will be possible in sheltered locations east of Highway 101 in Monterey and San Benito Counties. While there's not great consensus amongst guidance/models, the potential will be there for fog to develop tonight. The limiting factor will likely be cloud cover as it would allow for less efficient radiative cooling.
..issued at 236 AM PDT Tue Oct 14 2025 (Wednesday through Monday)
Global ensemble clusters are in agreement that upper-level shortwave ridging will nose in from the Eastern Pacific Ocean by Wednesday. At the surface, high pressure will also nose in from the Eastern Pacific Ocean and build into the Pacific Northwest through Thursday. This will translate to a northerly (drying) gradient developing across California. By Friday and into Saturday, the high pressure builds into the Great Basin while a coastal trough develops off the coast of California. This will result in light offshore flow for these two days. Fortunately, just coming off the heels of a widespread wetting rain event, this warming and drying trend will not be a fire weather concern. Global ensemble clusters are in agreement that heights will fall Sunday with an approaching upper- level longwave trough. Confidence quickly plummets by Monday as there is near split percentages on if troughing will continue to dig into the region or if high pressure will rebuild. Nonetheless, at least expect an increase in cloud cover and wind towards the end of the forecast. While the current forecast is dry, there is potential for rain returning to the forecast with ECMWF and GFS total precipitation ensemble spread showing a three inch disparity.
(18z TAFS) Issued at 1056 AM PDT Tue Oct 14 2025
Deep upper low pressure system currently located off the Central Coast will continue to meander towards the southeast. Mixed skies thru today with SCT Cu and stratus. Light rainfall and shower activity anticipated for North Bay terminals through the early afternoon, migrating to the East Bay region by the early evening. Patchy MVFR cigs anticipated tonight as temps cool and showers end. High confidence in clearing skies from west to east by the sunrise hour Wednesday.
Vicinity of SFO, VFR thru most of the period with the exception of the overnight hours where cigs may lower to MVFR. Any cigs that do develop will likely scatter out by sunrise Wednesday. Most shower activity expected to remain east of the terminal and approach. However, keeping VCSH in forecast with the best chance 00-03Z. VFR thru Wednesday with isolated SCT/BKN Cu.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, Mostly clear today with SCT Cu being the biggest factor. Low chance of isolated showers this afternoon. Moderate confidence in VFR thru the rest of the period. Once again, biggest impact Wednesday will be SCT/BKN Cu moving off high terrain.
(today through Sunday) Issued at 1056 AM PDT Tue Oct 14 2025
Surface low currently centered near Point Sur will promote isolated showers across the waters today. Cannot rule out an isolated thunderstorm south of Pigeon Point through this afternoon. Hazardous seas will persist with seas over 10 feet over the outer waters. Overall conditions will gradually improve late Tuesday into Wednesday.
Ca, None. PZ, Small Craft Advisory until 3 PM PDT this afternoon for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.
