Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
927 FXUS66 KSGX 061645 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 845 AM PST Sat Dec 6 2025 .SYNOPSIS... Warmer this weekend with the potential for patchy dense fog near the coast tonight and again Sunday night. Much warmer next week with highs 10-15 degrees above normal and periods of weak to locally moderate Santa Ana winds, strongest on Tuesday. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .Morning Update... Satellite is showing cloud free skies across Southern California. Temperatures this morning are starting out in the lower 40s in the wind sheltered valleys and locally in drainage basins. Coastal areas and foothills above the inversion are experiencing a milder start in the 50s. Temperatures remain on pace to reach into the lower 70s for much of the coastal basin for a few hours this afternoon. Coastal fog development tonight remains uncertain and patchy at best. No changes currently to the forecast. Previous discussion (2:20 AM Saturday)... Skies remain clear this morning with light winds across the region. Pressure gradients will be nearly neutral to the local deserts through Sunday morning, allowing for a weak sea breeze to develop this afternoon. With the return of this weak onshore flow and a forecasted weak coastal eddy tonight, we could see a development of dense fog over the coastal waters and locally into the coastal areas tonight into Sunday morning. Weak offshore flow kicks back in on Sunday morning, helping to clear out any fog. Patchy dense fog may briefly return again Sunday evening before slightly stronger offshore flow develops Sunday night. Aside from that, there will be gradual warming through the weekend as an upper level ridge of high pressure begins to build in from the west. High temperatures today will be around 3-7 degrees above normal, increasing to around 5-10 degrees above normal for Sunday. Next week can be summed up with warm and dry. The upper high slowly shifts east through the week, directly overhead by Friday. At the surface, mostly weak Santa Ana winds will prevail, becoming locally moderate on Tuesday morning as surface gradients peak. With no upper level support, winds will remain confined to the usual passes, canyons, and coastal slopes and follow a diurnal pattern, strongest in the mornings and then weakening during the afternoon. On Tuesday morning, northeast to east gusts in the wind prone locations will generally peak around 30-45 mph. Monday and Wednesday through Friday will see peak gusts closer to 20-35 mph. Only minor daily fluctuations in temperatures is expected, with highs generally 10-15 degrees above normal each day Monday through Saturday. Dry air and weak winds overnight will allow for decent cooling, so HeatRisk remains low. For the valleys and deserts it will very much be a winter in the morning, summer (highs in the low 80s) for a few hours in the early afternoon, and fall in the evening sort of pattern. The forecast becomes a little more uncertain towards next weekend with the upper high potentially beginning to weaken or break down, influencing how much cooling we`ll see and whether or not onshore flow will return. Still no signs of precipitation around here until the second half of the month. && .AVIATION... 061630Z....Low clouds/fog have the potential to develop along the immediate coast after 03Z Sun. Chances are 10-20% in San Diego County through 12Z Sun and 30-40% in Orange County through 19Z. Areal coverage of any low clouds/fog will be patchy with bases less than 500 ft and visibility 1 mile or less. Confidence is not high enough in VIS restrictions to include fog in the TAFs at coastal sites at this time. VFR conditions will prevail for inland areas through the TAF period. && .MARINE... No hazardous marine conditions are expected through Thursday. && .BEACHES... Morning high tide is predicted to be 6.5 to 7 ft on Sunday at 10 AM in La Jolla and at 9:50 AM in Newport Beach. Astronomically high tides may result in tidal overflow in normally dry beach areas. High tide is predicted to fall below 6 ft by Monday. && .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...Westerink AVIATION/MARINE/BEACHES...CO