Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
703 FXUS66 KSGX 191221 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 521 AM PDT Wed Jun 19 2024 .SYNOPSIS... A warming trend will continue into the weekend with high temperatures on Saturday as much as 8 to 12 degrees average for the inland valleys onto the lower coastal mountain slopes. The coast and valleys may be a few degrees cooler for the early and middle part of next week. Nights will be warmer over the weekend into early next week for the lower deserts with a shallow increase in lower level moisture. The marine layer will keep coastal areas cooler with areas of night and morning coastal low clouds spreading into portions of the valleys late each night. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Friday)... The trough of low pressure will slowly weaken with a warming trend continuing into the weekend. With the warming, high temperatures will generally be slightly above average near the coast to 4 to 8 degrees above average for the mountains, deserts, and inland valleys with highs on Friday of 605 to 112 for the lower deserts and in the 90s to around 100 for the Inland Empire. The marine layer will remain around 2000 to 2500 feet deep with night and morning coastal low clouds extending into portions of the inland valleys late each night. && .LONG TERM (Saturday through Tuesday)... High pressure to the southeast will expand into southern California with a trough of low pressure remaining in the vicinity of the West Coast to the north of the area. For most areas the warming will continue into Saturday. The 07Z NBM is not quite as hot for Palm Springs and Thermal on Saturday with high temperatures of only 110 with a dewpoint as high as 61 for Thermal late Saturday morning and 65 on Sunday morning. With the moisture, nights will be warmer for the lower deserts. Days in the lower deserts will still be quite hot, but not quite as hot absent the modest increase in moisture. The Heat Risk could near Excessive Heat Warning thresholds for the lower deserts as early as Saturday and continuing through at least the middle of next week. && .AVIATION... 190930Z...Coast/Valleys...Areas of low clouds with bases 1400-1900 ft MSL and tops to 2300 ft MSL will continue to spread 15-20 mi inland this morning. There is a 50-60 percent chance of a CIG at KONT 12-16Z. Local vis 2-4 SM in BR/HZ where clouds near terrain in the valleys. Clouds clearing inland 15-17Z and near the coast 17-19Z though some beaches may remain BKN-OVC through the afternoon. Low clouds beginning to spread back inland after 20/01Z and moving 15-20 mi inland by Thu morning. Bases will be near 1000 ft MSL with tops to 1500 ft MSL. Mountains/Deserts...Mostly clear with unrestricted vis through Thu morning. && .MARINE... No hazardous marine weather conditions are expected through Sunday. && .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...17 AVIATION/MARINE...SS