342 FXUS66 KMTR 052306 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 406 PM PDT Sat Jul 5 2025 ...New AVIATION, MARINE... .KEY MESSAGES... Updated at 131 PM PDT Sat Jul 5 2025 - Temperatures remain below seasonal averages into early next week. - Marine layer increases and expands farther inland for end of the weekend and continues into early next week. - Gradual pattern change which will bring a warming trend starting Wednesday. && .SHORT TERM... Issued at 131 PM PDT Sat Jul 5 2025 (This evening through Sunday) Near zonal flow will give way to an upper level low that has formed off the Northwest Coast of CA this afternoon. This will slowly slink meander to the south and then look to hold off our coast through Sunday. This will lead to seasonably cool temperatures continuing and lead to a deepening marine layer. For now, mostly clear skies are observed across much of the Bay Area and Central Coast with stratus clinging to the San Francisco/San Mateo coasts. Stratus is expected to fill back in later this evening and into tonight, and should seep into coastal valleys by Sunday morning. The clouds should retreat to the coast by late Sunday morning or early Sunday afternoon. && .SHORT TERM... Issued at 131 PM PDT Sat Jul 5 2025 (This evening through Sunday) Near zonal flow will give way to an upper level low that has formed off the Northwest Coast of CA this afternoon. This will slowly slink meander to the south and then look to hold off our coast through Sunday. This will lead to seasonably cool temperatures continuing and lead to a deepening marine layer. For now, mostly clear skies are observed across much of the Bay Area and Central Coast with stratus clinging to the San Francisco/San Mateo coasts. Stratus is expected to fill back in later this evening and into tonight, and should seep into coastal valleys by Sunday morning. The clouds should retreat to the coast by late Sunday morning or early Sunday afternoon. && .LONG TERM... Issued at 131 PM PDT Sat Jul 5 2025 (Sunday night through next Friday) A closed low should sit off just to our west through the early portion of the work week, which will allow the marine layer to deepen. Look for nighttime and morning clouds through midweek, with perhaps some coastal drizzle Monday night and again Tuesday night. A pattern change will start around Wednesday which is when ensemble and cluster analysis show the ridge over the Desert Southwest strengthening. Temperatures should increase for the later portion of the week, with Thursday and Friday looking to be the warmest at this time. It`s still too early to say how warm we`ll get as this time, especially since models struggle with how strong the ridge will get. && .AVIATION... (00Z TAFS) Issued at 404 PM PDT Sat Jul 5 2025 Currently VFR at all terminals with stratus off the coast. The marine layer is currently being observed at 1,200 feet on the Fort Ord profiler. A cutoff low off the coast will promote onshore winds, the deepening of the marine layer, and coastal drizzle. Moderate to high confidence on all terminals deteriorating below VFR tonight - likely low-end MVFR to IFR ceilings for all but the coastal terminals of HAF, MRY, and SNS which are expected to have LIFR ceilings - with confidence lowering the farther inland the terminal is. Widespread VFR is likely by tomorrow afternoon (with the exception of HAF which will likely remain MVFR) with stratus sticking close to the coast. Vicinity of SFO...Currently VFR with westerly flow. High confidence in sub-VFR ceilings returning to the terminal tonight with both HREF and NBM giving a 90% chance - the ceiling will likely be low- end MVFR to IFR. High confidence in VFR prevailing by tomorrow afternoon. Westerly winds will prevail through the TAF period. SFO Bridge Approach...Low clouds will begin to filter in to the San Mateo Bridge Approach by 00Z with high confidence in them clearing by tomorrow afternoon. Monterey Bay Terminals...Currently VFR with westerly flow at both terminals. High confidence in the return of sub-VFR ceilings to the terminals tonight with both of them ultimately degrading to LIFR. Brief VFR is expected tomorrow afternoon with stratus sticking close to the coast. Westerly winds will prevail through the TAF period. && .MARINE... (Tonight through next Thursday) Issued at 404 PM PDT Sat Jul 5 2025 Moderate seas and a fresh to strong northwesterly breeze will continue through early Sunday. Winds will continue to ease on Sunday to a moderate to fresh breeze and then become southerly while diminishing into Monday. Northwesterly winds increase and significant wave heights build beginning late in the upcoming week. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay- Pigeon Pt to Pt Pinos 0-10 nm. Small Craft Advisory until 9 AM PDT Sunday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm. Small Craft Advisory until 3 AM PDT Monday for Pt Arena to Pt Reyes 10-60 NM. && $$ SHORT TERM...KR LONG TERM....KR AVIATION...Sarment MARINE...RGass 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