573 FXUS66 KMTR 091206 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 506 AM PDT Sat Aug 9 2025 ...New AVIATION... .KEY MESSAGES... Updated at 339 AM PDT Sat Aug 9 2025 - Moderate HeatRisk continues through Monday for portions of North, East, and South Bay counties and interior Monterey and San Benito counties. - Elevated fire weather concerns persist given the warm and dry conditions, with breezy winds each afternoon and evening. - Pattern change Tuesday, with cooler weather and coastal drizzle returning to the forecast. && .SHORT TERM... Issued at 339 AM PDT Sat Aug 9 2025 (Today and tonight) Not much change to the forecast, with the marine layer looking more expansive this morning. How so, you might ask? Well, the stratus has slinked its way up the coast and has begun to infiltrate the a few valleys. The Fort Ord profiler shows the marine layer around 1000- 1200ft with stratus blanketing the Salinas Valley. Expect the stratus to blossom a bit more tonight for some interior locations, though it will be short lived as it mixes out this morning. Another warm and mostly sunny day will be on tap for much of the region. Moderate HeatRisk continues for portions of North, East, and South Bay counties and interior Monterey and San Benito counties. High temperatures in these areas will be in the 90s to near 100, while areas in Minor HeatRisk have temperatures span from the 60s to the 80s. Those cooler temperatures will be closer to coast and where the marine layer and perhaps lingering stratus holds. As we continue to have this stretch of warmer weather, continue practicing heat safety. Some of you may be experts by now after reading these discussions, but if you're new here, don't worry, we got you! You can beat the heat by: wearing sunscreen, taking breaks, staying hydrated, reducing your time outdoors, wearing lighter or && .LONG TERM... Issued at 339 AM PDT Sat Aug 9 2025 (Sunday through Friday) Upper level high holds through the weekend and into early next week. This means, we'll continue to see the forecast on repeat. Patches of Moderate HeatRisk is expected for portions of the East, South, and North Bay while Minor HeatRisk is expected elsewhere through Monday. Additionally we'll continue to see the marine layer and associated stratus form each night, with any inland penetration eroding quickly and leading to warmer weather. The pattern begins to change on Tuesday, which is when we'll start to see a reprieve in temperatures thanks to an upper level trough breaking down the ridge. We'll likely see a deeper marine layer and more coastal drizzle and fog midweek too. && .AVIATION... (12Z TAFS) Issued at 505 AM PDT Sat Aug 9 2025 Currently a mixed bag of LIFR-VFR at the terminals with a marine layer of about 1,400 feet. An increase in low level moisture has allowed for a healthy blanket of stratus and lower ceilings and visibilities than yesterday morning. High confidence in widespread VFR by the afternoon with low stratus sticking close to the coast. Vicinity of SFO...Currently MVFR with westerly flow - MVFR category is due to mist which can be seen on the SFO camera. More optimistic on the terminal remaining VFR (at least ceiling wise) this morning as compared to yesterday morning due to satellite trends. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...Currently LIFR and calm at MRY and IFR with southerly flow at SNS. High confidence (70%) on ceilings on the cusp of LIFR/IFR returning to both terminals tonight. && .MARINE... (Today through Thursday) Issued at 339 AM PDT Sat Aug 9 2025 A gentle to moderate breeze will prevail through Wednesday with strong gusts through the Delta due to the afternoon sea breeze. Seas will abate today with widespread moderate seas expected by Monday. && .FIRE WEATHER... Issued at 920 AM PDT Fri Aug 8 2025 Solid nocturnal drying over the highest peaks last night. Chews Ridge in the Santa Lucia range above Big Sur "recovered" early in the night then steadily dropped below 20% by 4 AM. Needless to say, areas like that would be consider poor on humidity recovery. Thankfully, winds were not overly strong, just some low end gusts. That being said, expect elevated fire weather concerns to persist through Monday given interior heat, low humidity, and daily afternoon wind gusts. Finer fuel/grass/veg fires seems most likely. MM && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...Small Craft Advisory from noon today to 11 PM PDT this evening for SF Bay N of Bay Bridge. Small Craft Advisory until 9 AM PDT this morning for Pt Arena to Pt Reyes 10-60 NM. && $$ SHORT TERM...KR LONG TERM....KR AVIATION...Sarment MARINE...Sarment Visit us at www.weather.gov/sanfrancisco Follow us on Facebook, X, and YouTube at: www.facebook.com/nwsbayarea x.com/nwsbayarea www.youtube.com/nwsbayarea