Area Forecast Discussion
Issued by NWS San Diego, CA
Issued by NWS San Diego, CA
899 FXUS66 KSGX 062031 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 131 PM PDT Thu Jun 6 2024 .SYNOPSIS... Night and morning low clouds will extend across the coast and valleys each day through the next week. Hot conditions continue across the deserts through Friday before slight cooling develops region-wide this weekend. Slow warming develops early next week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... At 1 PM, low clouds extend around 5-10 miles inland. Some peeks of sunshine will be possible across the coast, but full clearing is unlikely. Only small changes in the "June Gloom" pattern are expected over the next week, with night and morning low clouds extending across the coast and valleys each day. Temperatures are heating up quickly in the deserts this afternoon- current temps are in the low-100s in the lower deserts and near 100 in the High Desert. Highs will top out 8-15 degrees above normal in the mountains and deserts, and near, to up to 5 degrees above normal across the coast and valleys. Highs will cool a few degrees in the mountains and deserts tomorrow as the ridge axis weakens and moves eastward. Slow cooling develops this weekend and the ridge axis continues to move eastward and a longwave trough approaches the West Coast. For Saturday, highs will top out near 70 at the coast, the mid-70s to mid-80s in the valleys, the upper-70s in the mountains, the mid-90s in the High Desert and the mid-100s in the lower deserts. Highs fall a few more degrees on Sunday. Ensemble guidance begins to diverge early next week. A closed low looks to break off from the mean flow Sunday or Monday and slowly meanders to the southwest before parking off the coast of Southern California or Baja California. The most noticeable impact from this will be increasing high clouds region-wide Sunday through the middle of next week. The low-levels look moisture starved so no precipitation is expected. To the north, a building ridge will lead to slow warming again on Monday and Tuesday. The major questions with the forecast are where the low ends up and how strong it is, and when and where the upper low is going to become absorbed into the mean flow. && .AVIATION... 061935Z...Coast and western valleys...Low clouds with bases 600-900 feet MSL with tops to 2000 feet cover most of the coastal areas. Local vis reduced 1-3SM over higher coastal terrain. Clearing is unlikely in the coastal areas this afternoon. Low clouds with similar bases/tops/vis and coverage will spread inland after 23Z and expand into western valleys overnight into Friday morning. Bases may rise slightly after 12Z Fri. Clearing on Friday will be similar to today with CIGs persisting over the coastal areas into Friday afternoon. Elsewhere...clear skies today and tonight. && .MARINE... No hazardous marine conditions are expected through Monday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...Heat Advisory until 9 PM PDT Friday for San Bernardino and Riverside County Valleys-The Inland Empire. Excessive Heat Warning until 9 PM PDT Friday for Apple and Lucerne Valleys-Coachella Valley-San Diego County Deserts- San Gorgonio Pass Near Banning. PZ...None. && $$ PUBLIC...EA AVIATION/MARINE...PG