664 FXUS66 KSGX 260950 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 250 AM PDT Sat Jul 26 2025 .SYNOPSIS... A trough of low pressure will continue cooler than normal weather through the weekend. High pressure will have greater influence on the area from the east, leading to near average temperatures by next week. Breezy west winds will continue this weekend across mountains and deserts, while the marine layer covers areas west of the mountains with low clouds each evening into the morning hours. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Today through tomorrow... High pressure conditions dominate the region, although there is troughing upstream, which has been influencing SOCAL and providing us with relatively cooler temperatures and below the seasonal average for this time of year. This will allow for highs today to be the coolest for the week. Low clouds will begin to scatter out by later this morning from east to west, and there could be some of these clouds sticking around along portions of the coastal areas and periodically going broken throughout the afternoon. The unseasonably cooler temperatures may also allow for some record lows for today and tonight. Tomorrow will be slightly warmer as the trough begins to fill an become absorbed back into the longwave trough to the north. Monday through Friday... By this period in the forecast, there will be a very slow and gradual amplification and shift in the ridge axis over the desert southwest, which will begin to edge ever so slightly toward the region throughout the week and also allow for temperatures to return to being closer to the seasonal average by the middle of the week. the marine layer will also begin to thin and lower during this time. Conditions will remain dry as the monsoonal moisture plume remains confined far enough east that the mountains and deserts will remain storm- free through then. && .AVIATION... 260930Z....Coasts/Valleys...Low clouds have filled inland through about 15-20 miles this morning, with some now stretching into the southern and western Inland Empire. Bases have lifted to about 2200- 2500ft MSL. 90% chance for CIGs to reach KONT between 10-16z with a 80% chance for KSBD for the same period. These clouds will scatter back out at 15-16z for inland valleys and eventually 17-18z for the coast. Mostly clear skies and VFR conditions prevail through the afternoon until low clouds redevelop this evening after about 01z Sunday. The low clouds will have bases around 2000-2500ft, initially favoring San Diego County when they first develop, but will spread northward into Orange County by 09z and into inland valleys by 12z. Mountains/Deserts...Mostly clear with VFR conditions through early Sunday morning. && .MARINE... No hazardous marine conditions are expected through Wednesday. && .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...Stewey AVIATION/MARINE...Munyan