Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
721 FXUS66 KSGX 040957 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 257 AM PDT Fri Apr 4 2025 .SYNOPSIS... The warming trend will continue through the weekend with Sunday high temperatures for the coast and valleys as much as 4 to 8 degrees above average. There is a slight chance of showers for this afternoon, mainly for the San Diego County mountains. Otherwise, dry weather is expected for the next week. Slightly stronger onshore flow for Monday and Tuesday with slight cooling for the coast and valleys and slower warming for the mountains and deserts. There will be additional warming for Wednesday and Thursday with high temperatures as much as 12 to 18 degrees above average for the mountains and high desert. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Sunday)... The large low pressure system over the western states will move slowly toward the southeast today, then more quickly eastward and into the plains on Saturday. The warming trend will continue through Sunday with Sunday high temperatures as much as 4 to 8 degrees above average for the coast and valleys with the lower deserts a few degrees above average. High temperatures on Sunday will range from around 70 near the coast to the upper 70s to mid 80s for the Inland Empire with the lower deserts in the mid 80s to around 90. There is a slight chance of showers for this afternoon, mainly for the San Diego County mountains, with isolated rainfall of one- quarter inch or less possible. Otherwise, dry weather is expected through at least the middle of next week. && .LONG TERM (Monday through Thursday)... A low pressure system moving inland to the north on Sunday night and Monday will bring slightly stronger onshore flow to southern California with slightly cooler high temperatures for the coast and valleys on Monday and Tuesday and slower warming for the mountains and deserts. Warming will resume for the coast and valleys for Wednesday and Thursday and continue for the mountains and deserts. With the warming, high temperatures on Thursday will be as much as 12 to 18 degrees above average for the mountains and high desert. High temperatures on Thursday will range from the lower 70s near the coast to the mid 80s to around 90 for the Inland Empire with the lower deserts in the mid 90s to around 100. NBM probabilities for the warmer portions of the Inland Empire to have high temperatures exceeding 90 on Thursday are around 80 percent while NBM probabilities for high temperatures for Palm Springs and for Thermal to reach 100 on Thursday are around 50 percent. && .AVIATION... 040930Z...Patchy low clouds near coast based 2000-3000 feet MSL through 16Z. Low confidence on more than intermittent cigs at coastal airports. Cumulus clouds based 6000-8000 feet MSL mainly over mountains and deserts 18-02Z, with a small chance of -SHRA mainly over mountains of San Diego County 20-01Z. Otherwise, mostly clear skies today and tonight. && .MARINE... No hazardous marine conditions are expected through Tuesday. && .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...17 AVIATION/MARINE...MM