393 FXUS66 KSGX 241057 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 357 AM PDT Tue Jun 24 2025 .SYNOPSIS... A warming trend will begin today and continue through next weekend with the greatest warming on Wednesday. High temperatures will warm from 5 to 10 degrees below average for inland areas today, to around 5 degrees above average for inland areas on Sunday. The marine layer will become a little shallower for the latter half of the week through the weekend with night and morning coastal low clouds extending inland only into portions of the western valleys. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Thursday)... The marine layer is near 2500 to 3000 feet deep with satellite imagery showing widespread low clouds over the coastal waters extending well inland across much of the Inland Empire and eventually across much of the San Diego County valleys. Low pressure aloft across the southwest states will weaken with a warming trend for today through the weekend. High temperatures today will warm slightly at lower elevations to around 5 degrees for the mountains with as much as another 4 to 8 degrees of warming on Wednesday for the mountains, deserts, and inland valleys and with another few degrees of warming on Thursday. With the warming, high temperatures will go from 5 to 10 degrees below average for inland areas today to around average for inland areas on Thursday. With the warming, high temperatures on Thursday will range from around 70 near the coast to the mid 80s to mid 90s for the Inland Empire with 104 to 108 for the lower deserts. The marine layer depth will gradually decrease to around 2000 feet by Thursday with night and morning coastal low clouds spreading inland into only as far as the western valleys. && .LONG TERM (Friday through Monday)... A slow warming trend will continue through Sunday with Sunday high temperatures around 5 degrees above average for inland areas, ranging from the lower to mid 70s near the coast to upper 80s to mid 90s for the Inland Empire with 108 to 112 for the lower deserts. The marine layer will be near 1500 to 2000 feet deep with night and morning coastal low clouds spreading inland into portions of the western valleys. && .AVIATION... 240900....Coast/Valleys...Low clouds have generally made it up to 20 miles inland for San Diego and Orange counties, with some patchy spread into the Inland Empire. Bases 1600-2200ft MLS and tops to 2500-2800ft. Most of the IE should eventually fill in through 12z with 50% chance of BKN CIGs reaching KSBD. -DZ and BR possible near the coasts briefly between 11z-15z. Low clouds retreat to the coast 16-19z. Clearing will likely occur at the beaches by early afternoon. Clouds redevelop after 01z Wednesday with similar or slightly lower bases, pushing into coastal land areas after 03z. Patchy clouds likely to reach into parts of the IE again by 10-12z Wednesday. .Mountains/Deserts...Clear skies and largely unrestricted VIS through Wednesday morning. && .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...Zuber