691 FXUS66 KMTR 081129 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 429 AM PDT Fri Aug 8 2025 ...New SHORT TERM, LONG TERM, MARINE... .KEY MESSAGES... Updated at 428 AM PDT Fri Aug 8 2025 - Moderate HeatRisk Friday through Monday for portions of North, East, and South Bay counties and interior Monterey and San Benito counties. - Seasonally warm conditions through the early part of next week. - Elevated fire weather concerns given the warming and drying trend coupled with daily afternoon/evening breezes. && .SHORT TERM... Issued at 428 AM PDT Fri Aug 8 2025 (Today and tonight) Satellite imagery this morning paints a different picture compared to yesterday. The main feature being the intrusion of stratus along the Central Coast and its interior valleys, while stratus hugs Marin, San Francisco, and San Mateo counties. The marine layer looks to be around 1000ft based of the Fort Ord profiler which matches some of the guidance for this morning. Farther north it appears to be closer to 500-1000ft, which is likely why we haven't seen stratus seep into the North Bay this morning. With the marine layer being shallow, expect stratus to retreat to the coast leaving much of the area with sunny skies by mid to late morning. These conditions combined with high pressure building into the region will lead to warmer conditions today. For those inland and less influenced by the marine layer, look for temperatures to soar into the 90s, with interior locations of East Bay, Napa, San Benito, and Monterey potentially cracking 100 degrees. Moderate HeatRisk is a bit more widespread given the slight increase in temperatures for these areas. With that being said, like yesterday I said in yesterday's extended discussion, if you're going to be outdoors, be sure to practice heat safety. Some pro tips include: wearing sunscreen, taking breaks, staying hydrated, and looking before you lock your vehicle. && .LONG TERM... Issued at 428 AM PDT Fri Aug 8 2025 (Saturday through Thursday) Upper level ridging builds over the weekend and holds into early next week. Patches of Moderate HeatRisk are expected for portions of the East, South, and North Bay while Minor HeatRisk is expected elsewhere. For those who have to work or are looking to enjoy the outdoors, be sure to practice heat safety. Wear sunscreen, take breaks, hydrate, and look before you lock your vehicle. Additionally, if you're seeking relief at the beach be mindful of an energetic surf zone with increased rip currents and sneaker waves. The ridge looks to break down Tuesday into Wednesday, as an upper level trough drops in from the north. This will lead to decreasing temperatures, for interior locations. && .AVIATION... (06Z TAFS) Issued at 1001 PM PDT Thu Aug 7 2025 IFR-LIFR stratus lingers at the immediate coast, mainly south of the Golden Gate, with significant inland development across the Monterey Bay and northern Salinas Valley. Confidence is low to moderate (30- 40% probability) of stratus coming through the Golden Gate overnight, but the area of greatest likelihood lies to the north of the main SF Bay terminals. As such, the TEMPO groups for BKN ceilings have been removed from the SFO and OAK TAFs. Any stratus that does form will dissipate rather early Friday morning with breezy onshore winds developing in the afternoon and evening. Warmer conditions and a compressed marine layer will keep stratus from developing very far inland through Friday night. Vicinity of SFO... VFR with breezy northwest winds through the next few hours. Low confidence in stratus formation at the terminal, thus have removed the TEMPO BKN group from the TAF. Any stratus that does form in the vicinity will dissipate by 16Z Friday. Breezy northwest winds return Friday afternoon and evening, with a very low confidence for return of a ceiling to the terminal Friday night. SFO Bridge Approach... Similar to SFO. Monterey Bay Terminals... IFR-LIFR through the night with possible fog at MRY. Stratus should scatter out through Friday morning. Light and variable winds prevail overnight before breezy onshore flow resumes Friday afternoon. A low to moderate confidence that stratus returns to the terminals Friday night. && .MARINE... (Today through Wednesday) Issued at 428 AM PDT Fri Aug 8 2025 Fresh to strong northwesterly breezes will wane through Saturday morning with a gentle to moderate breeze prevailing through Tuesday. Moderate to rough seas over the weekend will abate to widespread moderate seas by Monday. && .FIRE WEATHER... Issued at 1004 AM PDT Thu Aug 7 2025 Elevated fire weather concerns will persist through the weekend. The warming and drying trend combined with daily afternoon/evening wind pushes will yield near critical fire weather conditions. Simply put, conditions are ripe for an uptick in grass fires/small veg fires the next few days. Inland gaps/passes and higher terrain will be highest at risk given the lack of marine layer/coastal moisture influence. MM && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...Small Craft Advisory until 9 AM PDT Saturday for Pt Arena to Pt Reyes 10-60 NM. && $$ SHORT TERM...KR LONG TERM....KR AVIATION...DialH 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