Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
746 FXUS66 KSGX 151113 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 413 AM PDT Wed May 15 2024 .SYNOPSIS... Into next week, night and morning low clouds will cover much of the valleys with limited or slow afternoon clearing near the coast. There is a slight chance of light showers for the San Bernardino Mountains for this afternoon and early evening. The valleys will cool a few degrees today. Otherwise there will be slow warming into Friday and Saturday, slow cooling for Sunday and Monday, then slow warming for the middle of next week with the warmest high temperatures for Friday and Saturday of this week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Friday)... Satellite imagery shows widespread low clouds over the coastal waters extending well inland across all of the valleys and beginning to spread onto the lower coastal mountain slopes as the marine layer deepens to around 3500 feet. Cloud bases near the coast have risen to around 2000 feet. Absent some additional increase in the depth of the saturated cloud layer, any drizzle this morning should be exceedingly patchy. Into the weekend, night and morning coastal low clouds will extend well inland across all of the valleys with limited or slow afternoon clearing near the coast. Satellite imagery also shows clouds from mid level moisture moving westward across San Bernardino and Riverside Counties. There could be some virga or lighter showers from these clouds during this afternoon and evening. The greatest chances for any measurable precipitation are over the San Bernardino Mountains at 10 to 15 percent with the experimental FV-3 ensemble showing some light accumulations of less than one-tenth inch. High temperatures will cool slightly for the valleys today, when slowly warm for the coast and valleys for Thursday into the weekend. High temperatures for the deserts will continue to slowly warm and be warmest for Friday and Saturday at around 4 to 8 degrees above average. && .LONG TERM (Saturday through Tuesday)... Night and morning coastal low clouds will extended well inland across all of the valleys with limited or slow afternoon clearing near the coast. High temperatures will cool for Sunday and Monday, then slowly warm into the middle of next week but not be as warm for the inland areas as Friday and Saturday of this week. && .AVIATION... 150930Z...Coast/Valleys...Low clouds filling the coastal basin with bases 1800-2200 feet MSL and tops to 3200 feet. Foothill terrain locally obscured and inland vis 3-5SM. Scatter out 17-19Z, but with partial and intermittent scattering out at/near the coast. Low clouds begin to spread back inland after 23Z with bases 2000-2500 feet MSL and filling the coastal basin again. Mountains/Deserts...Cumulus over mountains based at 9000 feet MSL 18- 03Z, with isold SHRA 21-02Z. West winds will gust locally 25-35 kt through mountain passes into adjacent desert slopes after 23Z. Regionwide...SCT to locally BKN clouds at/above 12000 feet MSL today and tonight. && .MARINE... No hazardous marine conditions are expected through Sunday. && .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