Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
507 FXUS66 KSGX 302039 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 139 PM PDT Mon Jun 30 2025 .SYNOPSIS... Hot conditions will continue today, especially for the deserts. A few degrees of cooling is expected for all areas Tuesday, with additional minor cooling 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 the western valleys through the week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Mostly clear skies will prevail across the region this afternoon. Temperatures at the coast as of 1 PM are running similar to a degree or two warmer than 1 PM yesterday, with temperatures up to 5 degrees cooler than yesterday for the valleys. Temperatures in the deserts are running about the same to up to 4 degrees warmer than yesterday. Mostly moderate HeatRisk coverage this afternoon across the deserts, with local areas of major HeatRisk expected. It is recommended to be extra cautious if planning to be outdoors, and be sure to stay hydrated to avoid any heat-related illnesses. An upper level low off the coast of California nearly due west of Pt. Conception will propagate southeast tomorrow through Thursday. That will pull some mid to upper level moisture into Southern California mainly Tuesday and Wednesday. This will result in areas of high cloud coverage across the area and the development of cumulus clouds over the mountains. There is a 10 percent or less chance that any showers or thunderstorms develop. Only a few members of both the ECMWF and GFS ensembles show light precipiation in the mountains. High resolution models are showing an isolated light rain shower or two in the San Bernardino Mountains and northeast into portions of the High Desert Tuesday and Wednesday. Confidence is not currently high enough at this time to officially introduce a slight chance of showers into the forecast. For the 4th of July holiday through the weekend, temperatures will remain within a few degrees of average with dry conditions prevailing. Marine layer low cloud and fog coverage will remain persistent each night and morning into early next week with minor variations in depth. && .AVIATION... 302030Z....Coast/Valleys...Mostly clear skies with VFR conditions prevailing through this evening/tonight. As with the last few evenings, low clouds will be sluggish to reform and become uniform in coverage, with CIGs expected for the coastal TAF sites by 05-08z Tuesday morning. Similar bases expected tonight, likely 900-1400ft MSL. CIGs largely MVFR for KSAN/KSNA (70% chance for no IFR CIGs, but more likely below 1000ft AGL (80% chance) for KCRQ. Inland extent will also be similar to this morning, with clouds extending about 15 miles inland with the IE remaining mostly SKC. Rapid clearing Tuesday morning by 16-17z. .Mountains/Deserts...FU/HZ possible through the Banning Pass and into the northern Coachella Valley due to Wolf Fire near Banning. SW/W wind gusts 25-35 kts continue for the deserts and mountain passes this afternoon, leading to periods of MOD UDDFS in the lee of mountains/mountain passes. Winds gradually relax some late this evening but remain elevated in the wind prone areas like in the lee of Banning Pass. Otherwise, VFR conditions prevail through Tuesday morning. && .MARINE... Afternoon winds near 10 knots with gusts 15-20 knots near San Clemente Island each afternoon today through Wednesday. Otherwise, no hazardous marine conditions are expected through Saturday. && .BEACHES... Building southerly swell (190 degrees) Friday of about 3 feet at 14- 15 seconds could bring sets of breaking waves to 6 feet along southerly facing beaches. This long period elevated swell likely continues into the weekend. && .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