Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
532 FXUS66 KSGX 081027 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 227 AM PST Mon Dec 8 2025 .SYNOPSIS... Very patchy fog near the coast this morning. Warm and dry with periods of weak Santa Ana winds this week. The peak of the heat is expected to be Tuesday for coastal areas and Wednesday for inland areas. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Occasional light fog and isolated dense fog has been reported near the coast this morning. Offshore surface pressure gradients are strengthening, pushing drier air towards the coast and limiting areal coverage of any fog. Expect this trend to continue through the morning with the already sparse fog to eventually dissipate. Breezy northeast to east winds will develop below the passes and canyons later this morning and continue into tonight with peak gusts around 35 mph in the wind-prone locations. Otherwise warmer and dry today with high temperatures around 10-15 degrees above seasonal averages. The upper level high over the East Pac amplifies and expands eastward on Tuesday. Weak Santa Ana winds will continue, pushing high temperatures up to 15-20 degrees above normal west of the mountains, and around 10-15 degrees above normal in the mountains and deserts. Inland coastal areas and western valleys will likely see highs near the mid 80s. The upper high continues to shift east on Wednesday with even weaker offshore flow, which will generally be confined to the foothills. The return of a weak sea breeze in the afternoon will bring a little cooling to the coastal areas, while inland areas continue to warm. Both the upper ridge and offshore flow continue to weaken on Thursday with a bit more of a sea breeze in the afternoon, spreading cooling further inland west of the mountains with little change in high temperatures elsewhere. There is a minor bump up in offshore gradients and Santa Ana winds on Friday morning, though this has trended weaker since yesterday. It remains quite warm and dry on Friday with highs still around 10-15 degrees above normal for inland areas and 5-10 degrees above normal near the coast. The upper ridge finally breaks down over the weekend for gradual cooling Saturday through Monday, though high temperatures remain several degrees above normal. Onshore flow and potentially coastal low clouds and fog return over the weekend. && .AVIATION... 081030Z...Clear and VFR conditions will prevail today and tonight. Except isold fog near KSAN could briefly and intermittently reduce vis 1-5SM through 15Z. Pockets of northeast winds gusting 25-35 kts mainly in foothills and adjacent valleys after 20Z. && .MARINE... This morning, isolated patches of dense fog with visibility around 1 nautical mile. Otherwise, no hazardous marine conditions are anticipated through Friday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && $$ PUBLIC...SS AVIATION/MARINE...MM