Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
562 FXUS66 KSGX 061131 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 431 AM PDT Mon May 6 2024 .SYNOPSIS... Dry and much warmer through Tuesday with the marine layer becoming shallower. There will also be stronger and gusty southwest to west winds for the mountains and deserts for Tuesday afternoon and evening with the stronger gusts to 50 mph. Cooler for the deserts and warmer for the coast and valleys for Wednesday with weak offshore flow. Then slowly warmer inland through next weekend. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Wednesday)... A cold low pressure system over Utah will move quickly eastward into the Great Plains today with onshore flow weakening some across southern California today. High temperatures today will be much warmer than Sunday, around 5 degrees warmer near the coast to as much as 15 to 20 degrees warmer for the mountains. Even with the warming, high temperatures today will still be a few to around 5 degrees below average. Coastal low clouds will be much patchier this morning. Southwest to west winds for the mountains and deserts this afternoon and evening will not be as strong as those over the weekend with the stronger gusts to around 40 mph. A weak low pressure system moving quickly southeastward through the Great Basin for late Tuesday and Tuesday night will bring stronger onshore flow for southern California with periods of stronger and gusty southwest to west winds for the mountains and deserts for Tuesday afternoon and evening with the stronger gusts to around 50 mph. Tuesday high temperatures will be a few degrees warmer for the coast and valleys and around 5 degrees warmer for the deserts with high temperatures around average for the deserts and few degrees below average for the coast and valleys. The lower level flow will go briefly and weakly offshore on Wednesday with high temperatures for the deserts a few to around 5 degrees cooler than Tuesday with the coast and valleys a few to around 5 degrees warmer. && .LONG TERM (Thursday through Sunday)... Low pressure aloft will weaken across the area slightly for Thursday through Sunday with slow warming for inland areas. For the coast and valleys, there is greater spread in the marine layer depth and inland extent of the night and morning coastal low clouds. The deterministic NBM has high temperatures for the coast and valleys slightly cooler for Thursday, then a little warmer for Friday and Saturday. There is greater spread in the NBM high temperature guidance for the coast and valleys for Friday and Saturday with the greatest spread for the valleys on Saturday. && .AVIATION... 060930Z...Coasts/Valleys/Foothills...Patchy low clouds will occur anywhere in the coastal basin and foothills through 16Z with bases 2500-3500 feet MSL. Areas of low clouds to redevelop in coastal areas after 06Z into Tuesday morning, with bases around 1200-1800 feet MSL. Otherwise...Mostly clear skies with unrestricted VIS will prevail today and tonight. && .MARINE... No hazardous marine conditions are expected today 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...Small Craft Advisory until 3 AM PDT early this morning for Waters from San Mateo Point to the Mexican Border Extending 30 to 60 nm out including San Clemente Island. && $$ PUBLIC...17 AVIATION/MARINE...MM