Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
265 FXUS66 KSGX 100402 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 902 PM PDT Thu May 9 2024 .SYNOPSIS... Night and morning marine layer clouds west of the mountains will clear back to the coast each afternoon through Sunday. High temperatures west of the mountains will be similar each day through Sunday, while the mountains and deserts will see a few degrees of warming this weekend. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .Evening Update... Slow cooling continues across the region with many areas 50s and 60s, while the Coachella Valley sticks in the 80s. Low clouds have increased in coverage across portions of Orange County with offshore clouds beginning to fill and push onto areas further south. Clouds will fill most of the coastal basin this evening, a bit patchier across the Inland Empire. Clouds may a have a tougher time clearing to the coast tomorrow in San Diego County, so expect partly to mostly cloudy conditions from Oceanside to Imperial Beach. The large area pushing into the Great Basin will push closer to our region by tomorrow. Chances remain quite minimal on any shower formation across the northern mountains and high desert by Friday afternoon, but would not be surprised to see a weak shower or storm occur. We will continue to monitor this with the next forecast package. Otherwise, no major forecast changes with quiet and seasonal weather continuing this weekend into much of next week! .Previous Discussion (145 PM Thursday)... Cumulus clouds formed over the San Bernardino and Riverside County mountains this afternoon. They will reform again Friday and Saturday afternoon in the broad cyclonic flow around a closed low over the Great Basin. West of the mountains the skies cleared a little more slowly today in the deeper marine layer. They will reform in the coastal areas this evening and spread inland overnight. Over the weekend the marine layer turns a little shallower and low clouds will not spread as far into the valleys Saturday and Sunday. High temperatures west of the mountains will be fairly consistent through Sunday with coastal highs from 65-75 and valley highs from 75-85. Mountains highs in the 60s today will warm into the 70s by Sunday. High desert highs in the mid 70s today will warm into the mid 80s by Sunday. In the lower deserts, highs near 90 today will heat up to near 100 on Sunday. This temperature regime continues Monday through Wednesday as a weak Pacific trough moves inland across Southern California. && .AVIATION... 100400Z...Coast/Valleys...Areas of low clouds with bases 1800-2600 ft MSL and tops to 3500 ft will occur overnight, though some areas will have only TEMPO CIGs. Local VIS 1-4 miles will occur in BR, mainly in the valleys 07Z-16Z Fri, with local terrain obscurations in clouds. The valleys will clear 16Z-18Z Fri, with partial clearing near the coast 18Z-21Z Fri as some locations will have a BKN CIG 2100-2700 ft MSL Fri afternoon. Low clouds will spread inland Fri evening. Mountains/Deserts...SCT/BKN clouds will develop again Fri afternoon over the mountains with bases around 9000 ft MSL with local TCU possible. Otherwise, mostly clear skies will prevail through Fri evening with unrestricted VIS. && .MARINE... No hazardous marine conditions are expected through Tuesday. && .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...APR/Moede AVIATION/MARINE...Maxwell