Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
342 FXUS66 KSGX 231702 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 902 AM PST Sun Nov 23 2025 .SYNOPSIS... Mostly sunny and dry for the remainder of today. A gradual warming is expected through Thanksgiving, with high temperatures returning to above normal by the middle of the week. Weak to moderate Santa Ana winds Tuesday through Thanksgiving, peaking on Wednesday. Another trough of low pressure will bring cooler weather with a 15 to 35 percent chance of showers sometime next Saturday afternoon into Sunday. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... The low pressure system that brought precipitation to SoCal over the last couple of days has moved east into AZ. The return flow on the upstream site of the upper low is now producing dry northeast winds in the mid-levels over SoCal. Skies are sunny this morning with only a few low clouds over the coastal waters. Mostly light, diurnal slope winds this morning as sfc pressure gradients are weakly offshore. Temperatures in the coastal areas and valleys are mostly lower than at this time yesterday in the dry boundary layer air. Expect high temperatures to be a little below seasonal averages under sunny skies today. A pattern change will see the western US become dominated by a building ridge of high pressure aloft at least through Thanksgiving, along with periods of offshore flow as sfc high pressure moves into the Great Basin. This will bring dry conditions and a warming trend through midweek. The offshore pressure gradients will bring Santa Ana winds for Tuesday through Thanksgiving. The winds will be strongest on Wednesday with northeast to east winds gusting 35-50 mph in the wind-prone areas of the passes/canyons and coastal slopes. Humidities in the inland valleys will drop into the high teens to low 20% range but the fire danger will be mitigated by the rains over the last week. It looks like Wed and Thu will be the warmest days, with daytime high temperatures in the low deserts, valleys and coastal areas reaching the 70s to low 80s. High temperatures could be as much as 11-14 degrees above seasonal averages in the inland valleys. For Friday into next weekend...The ridge of high pressure will be weakened and displaced by an extensive area of low pressure. This will bring a return of cooler, unsettled weather with onshore flow, higher humidity and chances for widespread precipitation next Sat and Sun. There is still considerable uncertainty surrounding the track and timing of multiple shortwave troughs but at this time, about 55% of ensemble members show precipitation sometime between Sat and Sun. && .AVIATION... 231600Z...Mostly clear skies and VFR prevailing region-wide through Sunday evening. Coasts/Valleys...Isolated low clouds based 1000-1500 ft MSL will form in areas after 02Z Mon, becoming more widespread if still patchy along coastal and western inland areas after 06Z Mon. 40% chance for CIGs at KSAN/KCRQ by 06Z, KSNA by 10Z. Chance (30%) for cigs to approach into the vicinity of KONT after 10z. Scatter out beginning for valleys 16z Mon. VFR conditions continue for the mountains and deserts through Monday morning. && .MARINE... No hazardous marine conditions are expected through Thursday. && .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...PG AVIATION/MARINE...Westerink