675 FXUS66 KSGX 012031 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 131 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... At 1 PM satellite imagery was showing patches of low clouds lingering along the immediate coast, mainly in San Diego County, with high clouds over the mountains and deserts. Real-time observations were showing temperatures similar to a few degrees warmer than this time yesterday in the deserts. Moderate to locally major HeatRisk is expected in the deserts this afternoon. It is recommended to be extra cautious if planning to be outdoors, and be sure to stay hydrated to avoid any heat-related illnesses. 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... 012015Z....Coast/Valleys...Low clouds have cleared out of all of the coastal TAF sites but are lingering across the beaches of San Diego County this afternoon. These clouds will push back ashore earlier than the last few nights, brining CIGs to KSAN and KCRQ as early as 03z Wednesday, and eventually to KSNA by 09z. Bases continue to be around 1000-1400ft MSL with about 10-15 miles of inland extent. Clouds scatter back to the coasts by 16-18z Wednesday morning. .Mountains/Deserts...West winds gusting 25-35 kt through the passes and on the desert mountain slopes this afternoon and evening with associated MOD UDDFS over and east of the mountains. Strongest wind gusts between 00-06z Wednesday, with strong winds waning and becoming more restricted to susceptible mountain passes by 12z. Otherwise, VFR conditions prevail through Wednesday afternoon. && .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...CO AVIATION/MARINE/BEACHES...Munyan |