739
FXUS66 KSGX 262011
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
111 PM PDT Sat Jul 26 2025

.SYNOPSIS...
A trough across the West Coast will continue cooler than normal
weather through the weekend. High pressure will expand further
west, bringing in a warming trend by Sunday into Tuesday, with
temperatures staying near average through the end of next week.
Breezy west winds will continue this weekend across mountains and
deserts, while the marine layer provides low clouds at times west
of the mountains.

&&

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

A trough currently draped over the West Coast continues to provide
onshore flow and cooling across our region. The calendar may say
late July but temperatures across the area are more like that of
late May or early June. Widespread 70s and 80s are seen for areas
along and west of the mountains with highs nearing 100 degrees in
the lower deserts this afternoon. This troughing pattern will
dominate through the weekend with below average temperatures and
deep marine layer, leading to much of coastal basin to see low
clouds tonight into Sunday morning.

An area of high pressure across the Southern Plains will begin to
expand closer to our region, where heights will rise. This will
bring a more noticeable warming trend by Monday and Tuesday,
where temperatures will climb to seasonal averages. There is high
confidence that temperatures will go closer to 110 degrees across
the lower deserts and 90s for the IE and high desert. Confidence
lowers by the end of the week as the exact placement of the high
pressure system will determine how warm we become. For now, NBM
continues to be used to describe the latest thinking with
temperatures plateauing Tuesday into later next week. If the area
of high pressure expands further west, temperatures may need to be
increased a few degrees. Whatever occurs, moderate heat risk will
return to the lower deserts during this time period. It is summer
indeed, but make sure to take breaks if you must be outdoors!

&&

.AVIATION...
262000Z....Coasts/Valleys...Mostly clear skies and VFR conditions
prevail through late this afternoon until low clouds based 2000-2500
ft MSL redevelop this evening after 27/01Z. Clouds will spread first
into San Diego County when they develop, but will move northward
into Orange County by 09Z then into the Inland Empire by 12Z. Clouds
clear inland 27/15-17Z and for the coast 16-18Z.

Mountains/Deserts...Mostly clear with VFR conditions through Sunday.

&&

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

&&

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