615 FXUS66 KSGX 050903 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 203 AM PDT Fri Jun 5 2026 .SYNOPSIS... Warm today with high temperatures a few degrees above normal. Cooler over the weekend with more widespread marine layer low clouds. Elevated southwest to west winds during the afternoon and evening through the weekend. Minor daily temperature fluctuations Monday through Thursday of next week, with the potential for more significant warming late in the week. Night and morning low clouds will continue for the coastal areas and valleys. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Marine layer low clouds have filled in over the coastal areas and spread into inland Orange County and parts of the San Diego County Valleys, with clear skies elsewhere. Low clouds will spread slightly further inland through sunrise, potentially reaching the far west parts of the Inland Empire, before clearing back to the coast by late morning. Weak upper level ridging remains over the region today, bringing another warm day with high temperatures in the low to mid 70s along the coast, upper 70s to low 80s for inland Orange County and the western valleys, mid 80s to low 90s in the inland valleys, 80s in the mountains, upper 90s in the high desert, and around 105-108 in the low deserts. An upper level low currently off the coast of British Columbia will move southeast into the Pacific Northwest and amplify into Saturday, with a reinforcing low following a similar path Sunday into Monday. This will bring cooling across the region into the weekend with highs lowering to a few degrees below normal by Sunday. The marine layer deepens each night with low clouds and patchy fog spreading further inland, potentially covering much of the inland valleys by Sunday morning. This will also generate breezy southwest to west winds in the mountains and deserts where gusts will be near 35-45 mph during the afternoons and evenings, strongest on Saturday. While troughing remains around through the middle of the week, the upper trough becomes less amplified, allowing for minor warming across Southern California. Temperatures fluctuate slightly each day, but in general remain within a few degrees of normal. The marine layer becomes more shallow for less widespread night and morning low clouds. Ensembles remain in fairly good agreement with some form of troughing through Wednesday. By Thursday, around 55% of the members keep the trough over the western US, while the remaining members are more progressive and have the trough shifting eastward, allowing some ridging to move in from the west. This continues into Friday and Saturday, though as we get later into the week the upper ridge becomes the slightly more dominant solution, comprising around 58% of the ensemble space. The trough lingering would result in a continuation of cooler weather with highs around normal, while the ridging solution would result in more warming and less low clouds as we head into the end of the week. && .AVIATION... 050440Z...Coast/Valleys...Low clouds are making their way inland over the coastal areas and into the adjacent valleys with cigs currently between 1000-1500 ft MSL. Low clouds will continue to fill into the valley areas, stretching inland 20-25 miles. Bases are expected to lower briefly around 08-10Z 700-1000 ft MSL in SD and 14- 16Z in OC. Localized VIS reductions to 4-6 SM for inland valleys and higher coastal terrain will be possible, with lower VIS where clouds intersect higher terrain. Chances for low clouds have increased to 40-55% for cigs in and around KONT from 10-15Z. Low clouds will clear the valleys after 16-17Z and are expected to cling along most of the coast line through the rest of the period. Cigs will increase in height 17-19Z to 1200-1700 ft MSL. Low clouds will begin to shift inland after 02Z Saturday with similar bases expected. Mountains/Deserts...Expect clear skies and VFR conditions through the period. && .MARINE... No hazardous marine conditions are expected through Monday. && .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...SS AVIATION/MARINE...Villafane