Etiwanda, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

048
FXUS66 KSGX 070424
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
924 PM PDT Fri Jun 6 2025

.SYNOPSIS...
A deep marine layer persists for coastal and inland areas through
Saturday, with a shallower marine layer and valley/inland fog Sunday
through much of next week. Temperatures warm through the weekend,
peaking Monday and Tuesday, before a slow cooldown into the end of
next week.

&&

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

This evening...The marine layer remains quite deep at about 3500
ft. Low clouds already cover San Diego County from the foothills
to the beaches and practically all of Orange County. Low clouds
are also creeping into southern parts of the IE. The saturated
layer remains thick and some locations are reporting drizzle.
These conditions are likely to persist into Saturday morning.

From previous discussion...
A closed upper low off the coast of central CA will likely remain
in that general location through Sunday, allowing the thermal
ridge axis to extend from WA through NV and into AZ. This will
position 850mb temps over coastal and inland areas Monday and
Tuesday around 22-24C while deserts will see 850 temps 25-27C.
This indicates surface highs may push well above 105F for the
Coachella Valley and San Diego deserts by Monday, currently
looking to peak on Tuesday with highs potentially at or near
108-110F. Elsewhere, temperatures will be above-normal, especially
for inland areas, with 92-96F for the Inland Empire early next
week. The ridge shifts eastward Wednesday, but zonal flow aloft
sets in, limiting the cooldown for the end of the week. At the
same time, multiple shortwaves pass across northern California and
Oregon through the end of the week, not expected to do much in
the way of precipitation but a slight uptick in wind is possible
for the far northern areas, especially the High Desert.

A deep low moves down from Alaska on Thursday, with troughing
setting in over the area early Friday and into the weekend. High
temperatures will continue to fall and the marine layer deepens,
returning the region to at or below normal temperatures likely by
Friday. Long-range models are pretty well aligned, with the low
persisting along the Canadian coastline, with cooler weather
potentially prevailing through mid June. Welcome back to June
Gloom!

&&

.AVIATION...
070300Z....Coast/Valleys...Low clouds based at 1000-2000 ft MSL with
tops to 3300 ft MSL have moved into Orange and inland San Diego
counties this evening, and will continue to fill most of the coastal
basin by 10Z tonight, with vis reductions over higher inland
terrain. Areas of -DZ are expected 09-15Z which will bring periodic
vis reductions 3-5 SM in BR and occasional cigs lowering to 700-900
ft MSL. Clouds clear from the Inland Empire 16-18Z and from Orange
County 17-19Z, with cigs remaining in San Diego County along the
coast and up to 15 miles or so inland through the day. Low clouds
will again spread to similar inland extent with similar to slightly
lower bases after 00Z Sun.

Mountains/Deserts...Mostly clear skies and unrestricted vis tonight
and Saturday.

&&

.MARINE...
No hazardous marine conditions are expected today through Tuesday.

&&

.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...PG
AVIATION/MARINE...CSP