Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
389 FXUS66 KSGX 230513 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 913 PM PST Sat Nov 22 2025 .SYNOPSIS... Dry conditions expected to return Sunday. Locally gusty northerly winds will weaken overnight. A gradual warming is expected for next week, with high temperatures returning to above normal by the middle of the week. A weak Santa Ana is possible sometime mid-week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... At 9 PM a few scattered showers were lingering in the High Desert, Coachella Valley, and desert slopes of the San Bernardino and Riverside county mountains. Rainfall out of these scattered showers is light, with rainfall rates less than 0.10 inches. Showers will taper off over the next few hours with dry conditions expected for Sunday through much of next week. There are some lingering gusty northerly winds near the Cajon Pass where gusts are still in the 30 to 40 mph range with much weaker northeasterly winds elsewhere. Those winds are expected to slowly weaken into Sunday morning. From previous discussion issued 2 PM November 22... Sunday, skies clear and high pressure builds and amplifies over the western US, increasing high temperatures into the mid to upper 70s by Tuesday. Behind the larger trough moving into the Eastern US, a surface high pressure of around 1036 mbs will set up in the northern Great Basin, increase the inland-coastal pressure gradient and generating offshore winds as early as Tuesday afternoon according to high resolution guidance. Offshore winds currently are set to peak Wednesday, with moderate confidence for at least a weak Santa Ana Wind event. Current guidance suggests north and east winds sustained at 15-25 mph, gusting 35-45 mph and locally higher, targeting the west facing foothill slopes and below the Cajon Pass, similar to today. With high res guidance available through Tuesday afternoon, confidence in the wind intensity outline above is moderate. The upper-end scenario for a high wind intensity event is capped due to the lack of mid and upper level support and likely will remain confined to the passes/canyons and foothills. High temperatures Wednesday and Thursday will likely be capped as well in the Inland Empire due to the flow of this colder, but modified air due to adiabatic compressional warming. The highest maximum temperatures are most likely to set up in the valleys closer to the coast as a result, approaching near 80F in some spots. Beyond Thursday, ensemble solutions diverge on the track of an upper low into the western US. The prevailing guidance suggests that a cold upper level airmass will dive straight southward (then may even retrograde a bit), close enough to Southern California to tap into surface moisture and ring out a few showers for areas south of Orange County. A slight deviation in the track east or west could change the precipitation chances significantly. && .AVIATION... 230400Z...SCT-BKN high clouds based 8-12 kft currently will move off to the east by 12Z. Isolated -SHRA ending by 12Z for deserts and eastern portions of the mtns. VFR conditions expected area wide through Sunday evening. Patchy low clouds returning to coastal areas and western valleys after 03Z Mon. && .MARINE... No hazardous marine conditions are expected through Wednesday. && .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...CO AVIATION/MARINE...KW