Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
342 FXUS66 KSGX 180233 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 733 PM PDT Mon Jun 17 2024 .SYNOPSIS... A coastal eddy will keep a deep marine layer in place through Thursday with night and morning low clouds clearing to the coast each afternoon. Skies will be clear over the mountains and deserts. Over the weekend a strengthening ridge of high pressure over the Desert Southwest will bring hotter weather back to Southern California. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... While a dome of high pressure brings sweltering heat to the eastern half of the nation, a trough over the West will keep temperatures a little below average in California for mid June. This trough will also bring gusty west winds to the mountains and deserts which will keep the fire weather threat high. A Catalina Eddy over the coastal waters this week will keep the marine layer deep enough each day for low clouds to reach the valleys each morning before retreating back to the coast each afternoon. From Wednesday through Friday the ridge over the east retrogrades southwest toward Texas and brings some of the heat with it. Models show an elongated upper ridge settling over the south third of the nation next weekend, then becoming a somewhat stationary upper high over the Four Corners area early next week which will bring hotter weather to SoCal. && .AVIATION... 180235Z...Coast/Valleys...Low clouds beginning to move ashore at this hour. Bases are around 1700-2000 ft MSL with tops to 2300 ft MSL. Low clouds will spread 20-25 miles inland by 12Z, obscuring higher terrain with VIS locally 1-3SM where clouds and terrain intersect. Bases may briefly go below 1500 ft MSL but the probability of that is less than 30 percent. CIG impacts at coastal TAF sites expected 06Z-17Z, and 10Z-17Z at KONT and KSBD. Inland clearing expected 16Z-18Z and 18Z-20Z at the coast. Mountains/Deserts...FEW-SCT clouds at/above 20,000 ft MSL tonight into Tue morning. Gusty west winds continue across the mountains and deserts, strongest this evening when gusts 25-40 kt are expected with isolated gusts 45-50 kt below the San Gorgonio Pass. MOD-STG up/downdrafts over and east of the mountains through this evening. Winds slowly weaken tonight into Tue morning. && .MARINE... Northwest wind gusts up to 20 knots will be possible in the outer waters this evening. Otherwise, no hazardous marine conditions are expected through Friday. && .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...Moede AVIATION/MARINE...PG