824 FXUS66 KSGX 150947 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 247 AM PDT Sun Jun 15 2025 .SYNOPSIS... Inland heat peaking today with high temperatures 5 to 10 degrees above normal. Breezy west winds across the mountains and deserts each afternoon and evening, strongest on Monday. A slow cooling is expected through most of the week with highs generally 5 degrees above average through Wednesday and closer to normal heading into the end of the week. Night and morning low clouds and fog can be expected each day along the coast and will reach into portions of the valleys at times. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Low clouds have spread back into the San Diego county coastal areas and western valleys, with less coverage in Orange County. Elsewhere a few high clouds continued to move northeast over the area. Low clouds will slowly spread northward along the Orange County coast through the morning as a very weak coastal eddy develops, and for what seems like the first time in a long time, we will actually have total clearing of the low clouds this afternoon. Otherwise warmer today with highs 5-10 degrees above normal inland as an upper level ridge of high pressure strengthens over the Desert Southwest. There is a 50-70 percent chance of high temperatures over 100 degrees in the far inland portions of the Inland Empire and a 75-100 percent chance for lower elevations of the Mojave Desert. There is a 25-35 percent chance of highs of 115 or more in the low deserts. Breezy west winds will develop below the passes this afternoon and evening, strongest through the San Gorgonio Pass where gusts to around 40 mph are likely (80% chance). The upper level ridge begins to flatten as an upper trough moves inland across the West Coast. This trough will bring some cooling Monday as well as gusty west winds in the mountains and deserts again with local gusts to around 50 mph below the passes and 25-40 mph elsewhere. Subtle cooling continues on Tuesday though highs will still be around 5 degrees above normal. The marine layer will remain relatively shallow with low clouds and patchy fog confined to the coastal areas each night and morning. The upper ridge reamplifies over So Cal on Wednesday for brief warming. Ensembles are still in generally good agreement with the development of an upper trough off the coast Thursday, slowly progressing eastward through the end of the week for gradual cooling and a deeper marine layer with more widespread night and morning low clouds. && .AVIATION... 150930Z....Coast/Valleys...Low clouds based around 600-800ft MSL with tops near 1000ft MSL have filled in about 10 miles inland across San Diego County and are very gradually filling in across southern Orange County. VIS varying 0-5 SM near/within the cloud layer, with 1/2-3 SM favored for the coastal terrain and inland valleys while the immediate coast is closer to 5-6+ SM. Low clouds retreat back to the coasts around 15-16z, with full clearing expected by 17-18z. Low clouds redevelop tonight around 06z Monday initially across southern coastal San Diego County. Clouds spreading 5-10 miles inland and northward into southern Orange County by 09- 12z Monday. Bases likely a touch lower than this morning, around 400- 700ft MSL. .Mountains/Deserts...FEW-SCT high clouds and mostly unrestricted VIS prevails through early Monday. && .MARINE... Wind gusts up to 20-25 kts possible in the outer waters Monday afternoon, primarily near San Clemente Island. Otherwise, no hazardous marine conditions are expected through Thursday. && .BEACHES... A 3 foot southerly (190 degrees) swell at 17-18 seconds will continue to produce elevated surf of 3 to 6 feet with local sets up to 7 feet, primarily for Orange County and northern San Diego County beaches. A Beach Hazard Statement remains in effect through late Sunday evening. Swell and surf heights wane late Sunday into Monday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...Beach Hazards Statement through this evening for Orange County Coastal Areas. PZ...None. && $$ PUBLIC...SS AVIATION/MARINE/BEACHES...Munyan