Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
350 FXUS66 KSGX 182104 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 204 PM PDT Wed Sep 18 2024 .SYNOPSIS... A low pressure system from the northwest will bring chances for light precipitation for Thursday into Friday with more clouds from the coastal waters to the mountains. Low pressure will weaken with dry and much warmer weather for the weekend into early next week with high temperatures warming to a few degrees above average on Sunday and around 5 degrees above average on Monday. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM... High temperatures today will continue to warm to slightly higher than recent temperatures but still below seasonal averages. The next closed low pressure system will move south along the California Coast before finally coming on shore over the LA Metro area early Friday Morning. This system is expected to bring increasing clouds to the area but no significant precipitation throughout the day Friday. Up to 0.10 inch of rain will be possible with the heaviest shower. Thunderstorms will be possible over the higher terrain of San Bernardino, however no significantlyenhanced precipitation is anticipated with these higher lapse rates in the upper altitudes. && .LONG TERM... The center of low pressure over southern California on Friday will move into Colorado on Saturday with lingering low pressure across southern California on Sunday. There is greater spread across California for Monday through Wednesday of next week ranging from weaker low pressure to weaker high pressure. Dry and much warmer weather is expected for the weekend into early next week, but with increasing spread in the high temperature forecasts, especially beyond Monday. With the warming, high temperatures will go from a few to around 5 degrees below average on Saturday to a few degrees above average on Sunday and around 5 degrees above average on Monday and Tuesday. High temperatures for the inland valleys will go from mostly in the 80s on Saturday to the upper 80s to upper 90s on Sunday and the 90s to around 100 for Monday followed by a few degrees of cooling for Tuesday. && .AVIATION... 182000Z...Coast to mountain ridges...Very patchy low clouds are present in coastal regions this afternoon, mostly in San Diego County, with varying bases between 2700 and 3500 ft MSL. These will continue to break up slightly over the next few hours, but more widespread low clouds redevelop along the coast after 01Z this evening. Bases initially around 2000-2500 ft MSL will gradually rise early Thu morning to 2500-3200 ft MSL with tops to 3400-3600 ft MSL. Local terrain obscurations within that layer. Low clouds will move well inland overnight, filling in the entire coastal basin. Widespread cigs will partially scatter out 17-19Z Thu, but patchy low clouds may linger along coastal areas through the afternoon, especially in southern San Diego Co. Mountain ridges to Deserts... Mostly clear today and tonight. && .MARINE... No hazardous marine conditions are expected through Monday. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && $$ PUBLIC...Suk AVIATION/MARINE...CSP