Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
355 FXUS66 KSGX 250423 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 923 PM PDT Tue Sep 24 2024 .SYNOPSIS... Through the weekend, slightly below average temperatures are expected along the coast, with near to slightly above average temperatures for the valleys. Highs in the deserts will remain above average into early next week. Night and morning coastal low clouds will continue along the coast and into portions of the western valleys each night. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... At 9 PM, low clouds had filled in the San Diego County coast and were continuing to fill in the Orange County coast. Low clouds are expected to make it into the western valleys overnight, potentially into the western portions of the Inland Empire. Above average temperatures are expected for the deserts as a ridge of high pressure builds over the Four Corners region. The High Desert, Coachella Valley, and San Diego desert are close enough to the ridge for it to influence temperatures there. Highs in those locations will be 7 to 11 degrees above average through the weekend. The warmest days are expected to be Friday and Saturday. Make sure you`re staying hydrated and avoid strenuous outdoor activities during the hottest part of the day if you can. From previous discussion issued at 2 PM Monday September 24... High temperatures for the coast and valleys may be a few degrees cooler on Wednesday and Thursday, with night and morning coastal low clouds extending a little farther inland into the western valleys as the marine layer deepens. Not much change in high temperatures is expected for the mountains and deserts, although current model runs have trended warmer than previous runs. An extensive upper level low pressure trough will remain off the coast, with high pressure to the east bringing slight warming for Friday. A little cooler for Saturday and Sunday as that low pressure trough moves nearer to the California coast. High temperatures a few degrees cooler will spread inland on Saturday and Sunday, with Sunday high temperatures a few to around 5 degrees below average for the coast and valleys and around 4 to 8 degrees above average for the deserts. High temperatures for the lower deserts will be 100 to 105. Then a little warmer for the coast and valleys on Monday as low pressure along the coast weakens. && .AVIATION... 250330Z...Coasts/Valleys...Low stratus based near 800-1100ft MSL with tops to 1300ft MSL are gradually pushing inland this evening. These clouds may lower 200-300ft overnight and should fill into the San Diego County foothills and the far northwestern Inland Empire by 12z Wednesday morning. Low to moderate (~40%) confidence exists for CIGs to reach KONT after 11z. Visibility reductions near 6SM and locally down to 3-4SM possible along the coasts, and less than 3SM where clouds intersect inland terrain. Any clouds fog look to scatter/clear by 17-19z Wednesday, but could linger along/just offshore through the afternoon. Low stratus pushes back ashore after 00z Thursday with similar bases/tops. Mountains/Deserts...Low clouds approaching foothills in San Diego county overnight; otherwise, mostly clear through Wednesday evening && .MARINE...No hazardous marine conditions are expected through this weekend. && .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...Munyan