Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
348 FXUS66 KSGX 020401 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 901 PM PDT Tue Jul 1 2025 .SYNOPSIS... Minor cooling is expected each day through Thursday. A gradual warming is expected Friday through the weekend. Night and morning low clouds and fog are expected to remain persistent along the coast and into portions of the valleys through the week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... This evening...Pockets of elevated convection could continue for a few more hours over portions of the deserts and local mtns. The primary threat posed by the convective elements would be the occasional dry lightning strike. Any precipitation that falls will likely evaporate in the dry sub-cloud layer before reaching the ground. The marine layer remains at a fairly consistent depth and low clouds are forming in coastal San Diego County and will likely spread inland and northward into OC in similar fashion to last night. From previous discussion... A weak upper level low pressure system centered off the central California coast will move slowly inland into central and southern California on Wednesday, then weaken and move inland into Arizona on Thursday. That will help spread cooling inland through Thursday. High temperatures will gradually decrease each day, bringing temperatures on Thursday down to 4 to 8 degrees below average for the mountains and inland valleys. It will also pull mid to upper level moisture into Southern California. This will result in areas of high clouds over the mountains and deserts through Wednesday. Even with the influx in moisture, dry conditions are expected to prevail. For the 4th of July holiday through early next week, a slow warming will occur. By Monday, NBM chances for the low deserts to exceed 110 degrees begin to increase to around 40 percent. Similar chances for Tuesday. By Tuesday, most locations are expected to see high temperatures 2 to 5 degrees above average. Marine layer low cloud and fog coverage will remain persistent each night and morning for the coast and into portions of the valleys with minor variations in depth. && .AVIATION... 020315Z....Coast/Valleys...Low clouds with bases 1000-1500 ft MSL will fill in along the coast by 06Z, then spread 15-20 mi inland by 12Z. Local vis 3-5 SM in BR/HZ where clouds near terrain in the valleys, including VCTY KAJO and KCNO. Clouds clearing to the coast 15-18Z, then redeveloping around 03/03Z with bases near 900-1300 ft MSL. Otherwise a few clouds near 15,000 ft MSL and unrestricted vis through Wednesday evening. Mountains/Deserts...SCT clouds in the 10-15 kft layer and occasional virga/light showers continuing over the deserts through about 18Z Wednesday. Otherwise clear with unrestricted vis through Wednesday evening. && .MARINE... No hazardous marine weather conditions are expected through Sunday. && .BEACHES... Building southerly swell (190 degrees) of 3 feet at 14-15 seconds will generate elevated surf of 3-5 ft with sets to 6 ft along southerly facing beaches in addition to strong rip and longshore currents at all beaches Friday and Saturday. Swell and surf will begin to lower on 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...PG AVIATION/MARINE/BEACHES...SS