Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
557 FXUS66 KSGX 131041 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 341 AM PDT Mon May 13 2024 .SYNOPSIS... For much of the week, night and morning coastal low clouds will spread inland across much of the valleys with limited or slow afternoon clearing for the beaches. A weak low pressure system moving inland across southern California for Tuesday night and Wednesday could bring a few light showers to the mountains for Wednesday afternoon with the chance of measurable precipitation less than 15 percent. There will be warming for most areas for Thursday and Friday with Friday high temperatures as much as 5 to 10 degrees above average for the deserts. This will be followed by a cooling trend for Saturday through Monday with Monday high temperatures cooling to around average for the deserts with the coast and valleys a few to around 5 degrees below average. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Wednesday)... The marine layer will fluctuate around 2500 to 3000 feet deep for much of the week. Night and morning coastal low clouds will spread inland across much of the valleys with limited or slow afternoon clearing for the beaches. A weak upper level low pressure system well off the California coast will move inland through southern California on Tuesday night and Wednesday. This could bring a few light showers to the mountains for Wednesday afternoon with the chance of measurable precipitation less than 15 percent. NBM has the greatest chance for measurable rainfall in the San Bernardino Mountains on Wednesday afternoon of around 13 percent. The experimental FV-3 ensemble also shows some very light precipitation in portions of the mountains for Wednesday afternoon. High temperatures for the coast and valleys will cool slowly through Wednesday with not much change for the deserts. && .LONG TERM (Thursday through Sunday)... High temperatures will warm for most areas for Thursday and Friday. High temperatures for the deserts will warm to 5 to 10 degrees above average for Friday, to around 105 for Palm Springs. Then slowly cooler for Saturday through Monday with Monday high temperatures around average for the deserts and a few to around 5 degrees below average for the coast and valleys. && .AVIATION... 130930Z...Coast/Valleys...Low clouds with bases 1000-1300 feet MSL with tops to 2000 feet will continue to fill most of the coastal basin. Local obscuration of higher terrain and reduced VIS 0-5SM inland where clouds and terrain intersect. Expect clearing to the coast 15-18Z with only partial or intermittent clearing at the immediate coast. Low clouds with similar bases/vis to push ashore and inland after 01Z and spread inland overnight into Tuesday in similar fashion with similar coverage. Mountains/Deserts...Mostly clear with unrestricted VIS today and tonight. SCT/BKN clouds over the mountains with bases around 9000 feet MSL 18-02Z. West winds gusting locally 25-35 kts through mountain passes into adjacent desert slopes after 23Z. && .MARINE... No hazardous marine conditions are expected through Friday. && .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