Arrowhead Highlands, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

945
FXUS66 KSGX 082025
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
130 PM PDT Tue Oct 8 2024

.SYNOPSIS...
Subtle cooling into Wednesday but then remaining similar the rest
of the week as a weak upper ridge persists. Daytime temperatures
5 to 15 degrees above averages for inland areas until additional
cooling by Sunday and Monday. Marine layer will persist along the
immediate coast and dry conditions elsewhere.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

A weak elongated upper trough is dropping into Socal today. This
results in about 1C cooling at 850 mb as the trough just washes
out by Wednesday and weak upper ridging returns for Thursday and
Friday with 589 DM 500 mb heights. This all means little change in
sensible weather and still much above averages for inland areas,
just not as hot. Air mass over the deserts goes from 26C to 25C so
inland cooling is minor as well.

For the longer range next week, numerical weather prediction
is taking the upper trough north of our region and over Great
Basin and much better agreement. There is not a stronger Pacific
upper low that could cut off and close off over southern California
next week, so the uncertainty is now with that system but could
bring few showers and then some offshore flow.


&&

.AVIATION...
082030Z...Coast...Areas of low clouds and fog with CIGs 200-500 ft
MSL and local VIS continuing below 2 miles, will remain along the
beaches this afternoon before low clouds and fog spread up to 15
miles inland this evening, with onset at coastal airports 01Z-04Z
Wed. CIGs of 100-500 ft MSL and VIS 0-3 miles will prevail, with
some coastal airports, including KSAN/KCRQ/KSNA having a greater
than 80 percent chance of VIS below 1 mile at times. Clearing times
are most likely to be between 15Z-17Z Wed, except later near the
beaches.

Valleys/Mountains/Deserts...Mostly clear skies with unrestricted VIS
will continue through Wed.

&&

.MARINE...Areas of dense fog with visibility 1 nm or less will
continue at times through Wednesday morning, with greatest coverage
between late evening tonight and early Wednesday morning.
Conditions could improve Wednesday afternoon. Otherwise, no
hazardous marine conditions are expected through Sunday.

&&

.FIRE WEATHER...
Posta wildfire along and south of I-8 burned fast yesterday in hot
conditions and near record dry fuels. Elevated fire weather
continues as we remain much above averages for inland areas but
not as hot.

&&

.CLIMATE...
Palm Springs had its first average day temperature of 100F for
October. The first 7 days are averaged 5 degrees hotter than
any previous October, at 96.9F.


&&

.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Excessive Heat Warning until 8 PM PDT this evening for
Coachella Valley-San Diego County Deserts-San Gorgonio Pass
Near Banning.

PZ...None.

&&

$$

PUBLIC/FIRE WEATHER...Tardy
AVIATION/MARINE...Maxwell