Canyon Crest, California Weather Forecast Discussion

846
FXUS66 KSGX 010345
AFDSGX
Area Forecast Discussion
National Weather Service San Diego CA
845 PM PDT Tue Sep 30 2025
.SYNOPSIS...
Warmer Wednesday and Thursday as high pressure builds in to the
southeast, but with high temperatures remaining below average.
Another low pressure system will move inland through California on
Friday with cooling of a few to around 5 degrees and slight
additional cooling for inland areas on Saturday. Then mostly
slight day to day differences for Sunday and Monday with high
temperatures remaining at least a few degrees below average.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
Evening update...
Water vapor imagery shows weak troughing across the western US ad
a short wave off the So Cal coast. Low clouds remain extremely
patchy over the coastal waters with clear skies across the region.
Latest HREF and local WRF keep most of the area clear overnight,
only bringing low clouds into Orange County and perhaps the
beaches of San Diego County Wednesday morning. No changes to the
forecast this evening.
Previous discussion...
For Wednesday and Thursday, the low pressure trough will move
inland and weaken. High pressure to the south will briefly
rebound, bringing warmer conditions with the marine layer
becoming a little shallower. High temperatures will warm a few
degrees on Wednesday and a few more degrees on Thursday but high
temperatures will remain around 4-7 degrees below average. High
temperatures on Thursday will range from the lower 70s near the
coast to the lower to mid 80s for the Inland Empire and the low
to mid 90s for the lower deserts.
For Friday into early next week...A low pressure system from the
Gulf of Alaska will move into CA with a closed upper low over
northern/central CA by Friday morning. The closed low will move
east and become an open wave by Sunday. This will bring general
cooling with temperatures about 5 degrees lower on Fri and further
cooling for Sat. Current indications are that Monday will be the
coolest day with temperatures as much as 10-12 degrees below
seasonal averages in the inland valleys. This system will also
bring a deeper marine layer and stronger onshore flow. Gusty
westerly winds will be likely for Friday into Saturday, mainly in
the mtns and adjacent desert areas. We will remain under the
influence of low pressure troughing through early next week,
although the forecast details will be less certain after Sat as
model solutions begin to diverge significantly.
&&
.AVIATION...
010330Z....Coasts/Valleys...Patchy low clouds may develop in San
Diego County after 06Z, but BKN cigs seem unlikely for KSAN and
KCRQ. Further north, low clouds based 1400-2200 ft MSL developing
after 09Z in Orange County. 20-30% chance BKN cigs reaching KONT
after 12Z. Any low clouds scattering to the coast by 16-18Z. SKC
through the afternoon with patchy clouds based 1000-1800 ft MSL
returning to coastal areas starting 03-06Z Thu.
Mountains/Deserts...Mostly clear and VFR conditions through Tuesday
evening.
&&
.MARINE...
No hazardous marine conditions are expected through Saturday.
&&
.BEACHES...
Elevated surf of 3-6 feet along south-facing beaches will slowly
diminish through tonight. Strong rip currents may linger through
Thursday for all beaches. The Beach Hazards Statement is set to
expire at 06Z tonight.
&&
.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement until 11 PM PDT this evening for Orange
     County Coastal Areas-San Diego County Coastal Areas.
PZ...None.
&&
$$
PUBLIC...SS/PG
AVIATION/MARINE/BEACHES...KW

NWS SGX Office Area Forecast Discussion