838 FXUS66 KSGX 230952 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 252 AM PDT Mon Jun 23 2025 .SYNOPSIS... High temperatures today will cool to 5 to 10 degrees below average for inland areas, then slowly warm during the week to around 5 degrees above average for next weekend. The marine layer will remain around 2500 feet deep into Tuesday with night and morning coastal low clouds spreading into portions of the Inland Empire. The marine layer will then slowly decrease in depth into next weekend with night and morning coastal low clouds only spreading inland into the western valleys. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Wednesday)... High temperatures for most areas will be a few degrees cooler than on Sunday as a weak upper level low pressure system moves southeastward across California today. High temperatures for today will be as much as 8 to 12 degrees below average for the mountains, valleys, and high desert, ranging from the mid to upper 60s near the coast to the mid 70s to mid 80s for the Inland Empire with the mid to upper 90s for the lower deserts. There will be a few degrees of warming on Tuesday with as much as another 4 to 8 degrees of warming for inland areas on Tuesday. With the warming, high temperatures on Wednesday will be near to around 5 degrees below average, ranging from around 70 near the coast to the 80s and lower 90s for the Inland Empire with 103 to 107 for the lower deserts. Early this morning, the marine layer is around 2500 feet deep with patchy low clouds over the coastal waters extending inland into the western valleys in San Diego County and portions of the Orange County coastal plain. Through sunrise, some increase in coverage is expected along with greater inland spread into the San Diego County valleys and into portions of the Inland Empire. The marine layer will remain around 2500 feet deep into Tuesday, then decrease in depth to around 2000 feet on Wednesday. Overnight coverage of low clouds is expected to gradually increase into Wednesday, but with not as much inland spread into the valleys for Tuesday night into Wednesday morning. && .LONG TERM (Thursday through Sunday)... High pressure to the south will continue the gradual warming trend into next weekend with high temperatures for next weekend around 5 degrees above average. High temperatures for next weekend will range from the lower 70s near the coast to the upper 80s to upper 90s for the Inland Empire with 108 to 112 for the lower deserts. The marine layer will continue to slowly decrease in depth to around 1500 to 2000 feet for late in the week through next weekend with night and morning coastal low clouds spreading inland into the western valleys. && .AVIATION... 220900....Coast/Valleys/Coastal Mountain Slopes...Satellite currently shows patchy low clouds based 1300-2100ft MSL along the San Diego coastline and western valleys, which will continue to spread inland and northward through 12z. Clouds may briefly spill into the western and southern portions of the IE. Low clouds clear to the coast 15-17z. 30% chance that BKN CIGs lingering through the afternoon at the coast. Patchy low clouds with similar to slightly lower bases begin to push inland again around 03-06z Tuesday. .Mountains/Deserts...Clear skies and largely unrestricted VIS through Monday evening. Wind gusts 25-35 kts Monday afternoon and evening with isolated gusts to 45 kts through mountain passes. Mod up/downdrafts near mountain ridges. Stronger gusts begin to subside by 04-06z Tuesday. && .MARINE... 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...17 AVIATION/MARINE...Zuber