117 FXUS66 KSGX 202045 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 145 PM PDT Wed Jul 20 2022 .SYNOPSIS... High pressure over the Southwest will continue the hot weather for the deserts into the weekend while the marine layer keeps coastal areas cooler with areas of night and morning low clouds and fog. The hottest weather for the deserts is expected on Thursday and Friday with an Excessive Heat Warning for the lower deserts. Increasing monsoonal moisture will bring chances for showers and thunderstorms beginning Sunday with inland areas not quite as hot early next week as moisture increases. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... At 1 PM, visible satellite showed abundant mid and high level clouds moving across SoCal from the south. High-level clouds are expected to continue at times over the next couple of days, potentially creating some great sunrises and sunsets! Low clouds will return to coastal areas this evening, but will likely be patchy. Strong high pressure will expand across the Southwest through the end of the workweek, bringing warmer temperatures mainly to the deserts. Temperatures are expected to peak on Thursday and Friday, when an Excessive Heat Warning is in effect for the Coachella Valley and San Diego deserts. High temperatures in those areas will be 113 to 116 degrees, with overnight lows only dipping down into the upper 80s to low 90s, elevating the heat risk. The High Deserts will also be quite warm as well, with temperatures of 100 to 105 degrees expected. The high pressure is forecast to weaken and shift north towards the end of the weekend and into early next week, decreasing temperatures in the deserts and putting SoCal back into more of a monsoonal flow pattern. Chances for showers/thunderstorms in the mountains and deserts return to the forecast beginning Sunday afternoon, with chances continuing each afternoon and evening through mid next week. NBM shows the highest chances for thunderstorms for the mountains and deserts on Sunday afternoon and Monday afternoon, though chances remain fairly low, around 15 to 20 percent. With the increase of moisture late this weekend and through mid-next week, high temperatures next week in the deserts won't be quite as hot as this week, with highs of 102 to 107 degrees forecast next week. && .AVIATION... 202000Z...Coast/Valleys...SCT to BKN200 high clouds continue this afternoon. The low CIGS from this morning have finally dissipated. More high cloudiness will continue through this evening which . may inhibit the development of low CIGS through this evening. The low CIGS should eventually re-develop however, after about 08Z, hut the presence of high clouds again lends low confidence to the forecast. Once low CIGS near the coast re-develop, expect 008-012 ft MSL to impact KSAN, KCRQ and KSNA between about 09Z-16Z Thursday. Mountains/Deserts...BKN200 tonight and Thursday. No visibility restrictions are expected. && .MARINE... No hazardous marine weather through Monday. && .BEACHES... A High Surf Advisory remains in effect through 8 AM Thursday for 4-8 ft surf from a long period 200 degree south swell of 3-5 ft at 17 sec. Highest surf on exposed southwest facing beaches. The San Clemente Basin buoy continues to report a 5 ft swell at 13-17 seconds. The swell and surf slowly decrease late this afternoon through Thursday morning. A smaller southerly swell will bring surf of 3-6 feet Thursday and Friday, highest occurring on the south- southwest facing beaches. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...Excessive Heat Warning from 11 AM Thursday to 8 PM PDT Friday for Coachella Valley-San Diego County Deserts-San Gorgonio Pass Near Banning. High Surf Advisory until 8 AM PDT Thursday for Orange County Coastal Areas-San Diego County Coastal Areas. PZ...NONE. && $$ PUBLIC...Connolly AVIATION/MARINE/BEACHES...Brotherton