


Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA
Issued by NWS San Francisco Bay Area, CA
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185 FXUS66 KMTR 281812 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 1112 AM PDT Thu Aug 28 2025 ...New AVIATION, MARINE... .KEY MESSAGES... Updated at 331 AM PDT Thu Aug 28 2025 - Near normal temperatures today and Friday, slightly warmer for the weekend - Quiet weather for the holiday weekend && .SHORT TERM... Issued at 331 AM PDT Thu Aug 28 2025 (Today and tonight) Offshore marine layer stratus is once again slow to develop early this Thursday morning. Persistent onshore flow continues to support a 2000ft marine layer with a relatively weak vertical temperature gradient, resulting in reduced stratus coverage than model guidance progged due to reliance on climatology. The interruption of offshore northwest surface flow should once again limit stratus redevelopment late this afternoon and evening. Bumped temperatures up along the coast from the Bay Area down to Monterey Bay to match closer to what was realized the past couple of days. && .LONG TERM... Issued at 331 AM PDT Thu Aug 28 2025 (Friday through Wednesday) Friday will be similar to today before a subtle pattern change sets in for the weekend. Expect one more day of interrupted stratus coverage along the coast with near normal temperatures across the interior. Low amplitude ridging for the weekend will result in slightly warmer temperatures, with a return to near normal temperatures for the beginning of next week. Increasing offshore northwest surface flow returns Saturday, which will bring cooler SST`s and increasing stratus development along the coast than we`ve seen the last few days. However, the marine layer will compress, limiting its inland penetration somewhat. Otherwise, sunny skies and light winds for our interior locations through the extended forecast. && .AVIATION... (18Z TAFS) Issued at 1111 AM PDT Thu Aug 28 2025 Nearly a picture perfect from space this morning as satellite shows mainly clear skies skies. Most sties are now reporting VFR conditions and this will likely hold through the early evening hours. The marine layer should remain a bit compressed, perhaps around 1000ft or less tonight, which should limit the inland expansion. Most confident that stratus returns to the coastline and then arrives for some interior valleys around or just after sunrise. Clearing of the stratus should occur by mid to late morning, with another afternoon of VFR conditions on Friday. Vicinity of SFO...VFR conditions should prevail until early Friday morning, with the main concern for this afternoon being a period of breezy west-northwest to westerly winds up to 20-25kt. Confidence is moderate that SFO will will see a period of MVFR cigs Friday morning, thus opted to go with a semi-persistance based forecast given the marine layer should be similar. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...Moderate confidence in stratus tonight, with stratus potentially arriving as early as 3Z and then holding through the overnight hours. Uncertainty is more so on timing and how low the CIGs go. Guidance hints at the possibility of IFR to LIFR near or shortly after sunrise. Skies should clear by late morning. && .MARINE... (Today through Tuesday) Issued at 1111 AM PDT Thu Aug 28 2025 Light to moderate winds and seas continue across the coastal waters through the end of the week. Seas build and fresh to strong gusts develop over the weekend bringing hazardous conditions across the coastal waters into the next work week. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && $$ SHORT TERM...JM LONG TERM....JM AVIATION...KR MARINE...KR 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