FXUS66 KSGX 242044 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 144 PM PDT Fri Oct 24 2025 .SYNOPSIS... Cooler and breezier conditions expected over the weekend. The marine layer will deepen, with low clouds and fog reaching into portions of the western valleys. Periods of offshore flow will bring warmer and drier weather with a shallower marine layer next week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Visible satellite at 1 PM was showing mostly clear skies with just a few patches of low clouds along the immediate coast. Low clouds are expected to become more widespread this weekend and are expected to reach into portions of the valleys each night and morning. A low pressure system moving inland to the north Saturday will displace the ridge currently over Southern California to the east. That pattern shift will bring cooler weather to Southern California. Highs this weekend will be a few degrees below average west of the mountains, but remain near average in the deserts. Zonal flow aloft and stronger onshore flow at the surface will produce gusty westerly winds, mainly for the mountains and deserts. Westerly winds with peak gusts 35 to 45 mph are expected each afternoon and evening with the strongest winds through wind prone passes. There is fairly good agreement that a ridge dominated pattern will set up over the Southwestern United States. High pressure aloft and periods of weak offshore flow will bring warmer conditions through next week. Wednesday will likely be the peak of the heat, with the ridge expected to weaken slightly as a minor shortwave trough moving inland to the north for the end of next week. Highs Wednesday will be up to 15 degrees above average for the inland valleys. The ridge- y pattern will also reduce the depth of the marine layer and restrict any low clouds/fog to the coastal areas. && .AVIATION... 241530Z...Coast and western Valleys...A few very patchy low clouds based at around 800-1200 feet MSL remain at the immediate coast. Low clouds based 700-1000 ft MSL will redevelop further and move back ashore after 02Z tonight, extending 10-15 miles inland, a bit beyond the I-405/I-15. VIS reduced to 1-5SM where clouds meet terrain and locally in inland valleys, highest confidence in timing around sunrise. 30% chance for VIS reductions below 2SM for KCRQ. VIS improves and low clouds scatter 16-18z. Inland Valleys/Mountains/Deserts...VFR through Saturday afternoon. SCT clouds AOA 10,000 feet MSL arrive from the north after 16z Sat. && .MARINE... No hazardous marine conditions are expected through Tuesday. && .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...CO AVIATION/MARINE...Westerink