Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
390 FXUS66 KSGX 021651 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 851 AM PST Sun Nov 2 2025 .SYNOPSIS... Locally dense fog this morning followed by above normal temperatures this afternoon. A trough of low pressure will develop along the West Coast this week, leading to a subtle cooling trend, a deeper marine layer, and breezy winds in the mountains and deserts. Dry weather will prevail with a warming trend late in the week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .Morning Update... Low clouds continue to retreat toward the coast. This morning`s sounding shows a continued shallow marine layer with a depth near 900 feet. This will make it harder for the atmosphere to mix out, where intermittent low clouds will occur at the beaches throughout the day. A trough to the north will begin to deepen the marine layer later today into Monday as models show low clouds and less fog moving further inland into the valleys, potentially into the Inland Empire by Monday morning. The forecast remains on track for the upcoming week. .Previous Discussion (230 AM Sunday)... Coastal low clouds and fog have pushed into the coastal areas and far western valleys this morning, with a bonus pocket of radiation fog beginning to develop western in the Inland Empire. Locally dense fog is occurring along the I-15 in the San Diego County. Elsewhere skies are clear. Low clouds and fog will clear towards the coast by late morning, followed by another warm and sunny day with highs around 5-12 degrees above normal inland. A weak upper level low will move eastward across So Cal later today, but the most this will do is bring some scattered high clouds later this afternoon. Weak troughing along the West Coast will bring a gradual cooling trend this week. The marine layer will slowly deepen with night and morning low clouds extending further inland, and dense fog becoming less of a concern. A short wave moving through the mean flow on Wednesday will bring an uptick in breezy west winds in the mountains and deserts. Wednesday now looks to be the coolest day with highs slightly below normal west of the mountains (highs in the 70s), but still a few degrees above normal in the mountains and deserts. An upper level ridge amplifies to the southwest on Friday as another low deepens over the East Pac, then shifts eastward over So Cal over the weekend. Weak offshore flow develops during this time as well as surface high pressure builds over the Great Basin. This will bring another round of warmer and drier weather with high temperatures several degrees above normal. While the next 7 days remain dry, all of the global ensembles are hinting at precipitation towards the middle of the month. && .AVIATION... 021600Z...Coasts/Valleys...Satellite shows low clouds based 700- 1100ft MSL are quickly pulling back to the coastline, with most coastal TAF sites expected to be VFR by 17z. VIS remains 3-6SM for most locations, improving over the next two hours. Clouds may linger just offshore through the afternoon before pushing inland again as early as 00z Mon with similar or slightly higher bases and similar inland extent. Bases may fall a bit overnight by 100-200ft generally after 07z. VIS will be 2-6SM, with locally lower at coastal terrain and areas around or above 600ft. 30-40% chance of a CIG at KONT, generally after 08z. Clouds should clear back towards the coast at a similar time as today, around 17z Mon. Mountains/Deserts...VFR conditions prevail through the period. && .MARINE... No hazardous marine concerns 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. && $$ UPDATE...APR PUBLIC...SS AVIATION/MARINE...Zuber