771
FXUS66 KSGX 262040
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
140 PM PDT Wed Jun 26 2024

.SYNOPSIS...
Minimal changes in the weather pattern are expected over the next
week. A ridge will break down slightly, leading to a deeper
marine layer and low temperatures a touch cooler by Friday. High
pressure is expected to return by early next week, warming things
back up to slightly above average levels away from the coast.

&&

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

A ridge centered over El Paso, Texas is peaking in strength today.
Moisture and instability are still present, so a very slight
chance of a shower or storm across the high desert later this
afternoon. Drying will continue as we get into Thursday and
Friday. This ridge will begin to weaken as a trough across the
northern portion of the West Coast deepens by Thursday into
Friday. This will have minimal impact our weather other than low
temperatures slightly cooler than we have seen over the past few
days, with more low cloud coverage west of the mountains. NBM
forecast lows look adequate for the Friday forecast period, which
will have the coolest overnight lows overall this week. Lows in
the low to mid 60s will be prevalent across areas west of the
mountains into the high desert, with lows in the upper 70s across
much of the lower deserts.

High pressure off the West Coast will begin to strengthen into
early next week. NBM probabilities for highs 115 or greater are
around 25-50% across the lower deserts with 60-80% chance of
triple digit heat for the Inland Empire and High Desert by Sunday
and Monday. Low temperatures by early next week will be back in
the 80s across the lower deserts and 65-70 for most areas below
5,000 feet. Global ensembles depict this high possibly
strengthening further into the week, which which would bring well
above average highs away from the immediate coast.

&&

.AVIATION...
262020Z...Coast/Valleys...Visible satellite shows lingering
scattered stratus bases 1300-2000 ft MSL along parts of southern and
northern San Diego Co. coast, but otherwise clear conditions. More
widespread low clouds redeveloping this evening, beginning to move
back into the SD coastal areas after 27/02Z, Orange Co. coastal
areas after 27/08Z, and spreading 15-20 mi inland by Thu morning.
Little change in bases/tops tonight, and the marine layer retreating
starting around 16Z. Otherwise FEW-SCT clouds at/above 15,000 ft MSL
through Thu morning.

Mountains/Deserts...SCT Cu with bases near 10,000 ft MSL have
developed along mountain crests this afternoon and will dissipate by
sunset. Otherwise FEW-SCT clouds at/above 15,000 ft MSL through Thu
morning. West winds with sfc gusts 25-40 kt developing across the
mountains and deserts this afternoon and evening, strongest through
the passes. MOD up/downdrafts over and east of the mountains. Winds
calm overnight then strengthen again Thu afternoon in similar areas
with sfc gusts 30-45 kt.

&&

.MARINE...
No hazardous marine conditions are expected through Sunday.

&&

.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 Thursday for Apple and
     Lucerne Valleys-Coachella Valley-San Diego County Deserts-
     San Gorgonio Pass Near Banning.

PZ...None.

&&

$$

PUBLIC...APR
AVIATION/MARINE...CSP