Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
612 FXUS66 KSGX 282025 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 125 PM PDT Tue May 28 2024 .SYNOPSIS... Fairly seasonal conditions will continue into Wednesday, with a slight warm up by Thursday and Friday for areas away from the coast due to weak high pressure. With this warming, the marine layer will shrink with some faster clearing each morning for valleys with better chances for clearing at the beaches. Weak troughing looks to come back into the picture by the weekend, which will cool inland areas a few degrees along with a bit more low cloud coverage nights/mornings west of the mountains. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Warm temperatures near 100 degrees are occurring across the lower deserts from Palm Springs to Borrego Springs. GOES imagery shows clouds sticking to the coast with subtle clearing starting to begin across Orange County. West wind will pick up this afternoon and evening across mountain passes into the deserts today with gusts near 25-45 MPH. Today will be the windiest day in these areas this week, slightly less so by Wednesday. The marine layer depth will decrease slightly on Wednesday with subtle warming inland and better chances for clearing at the beaches. High pressure across northern Mexico will shift further north by Thursday and Friday. This will shrink the marine layer even more with slightly warmer temperatures inland. NBM probability points to about a 30-40% chance in high temperatures over 105 degrees by this time in the springs of Borrego and Palm. This will lead to areas of moderate heat risk, so impacts will be felt to those sensitive to heat or without proper cooling/hydration. Heights will lower once again by the weekend with a few degrees of cooling for inland locales, where the region will be near average with breezy conditions for desert mountain slopes into adjacent desert regions. With this will also come a slightly deeper marine layer, with more low cloud coverage and patchy valley fog for areas like the Inland Empire each night and morning. && .AVIATION... 281940Z...Coast/Valleys...Limited or intermittent scattering is expected at the immediate coast this afternoon. Low clouds with similar bases/vis as last night, generally around 700-1400 FT MSL, will spread back inland after 02Z and into portions of inland valleys early Wednesday. Expect another slow round of clearing Wednesday morning, generally 16-18z for inland areas and 17-19z for the coast. Mountains/Deserts...Areas of W-SW surface gusts 30-40 knots on desert mountain slopes and locally into the deserts after 22Z. Otherwise...SCT high clouds this afternoon, but generally clear skies with unrestricted vis today and tonight. && .MARINE... No hazardous marine conditions are expected through Saturday. && .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...APR AVIATION/MARINE...Adams