Trabuco Highlands, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

606
FXUS66 KSGX 060343
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
843 PM PDT Mon May 5 2025

.SYNOPSIS...
Any remaining showers across the mountains and deserts will come
to an end this evening, with drier and warmer conditions
prevailing for the remainder of the week. Highs return to near
normal by Thursday, with highs 10-20+ degrees above normal by
Saturday when heat concerns may return. Early next week, cooler
weather will return with the arrival of the next system.

&&

Update: Any of the lingering showers have moved out of the CWA for
the most part. There still looks to be a surface low developing
during the morning hours tomorrow. This will allow for an
enhancement of the marine layer, and likely some drizzle for the
coastal and inland areas, especially along the immediate coastline
as the high res models suggest. Otherwise, high pressure will
continue to build back in as the ridge moves in over the region and
strengthens by later this week and into the weekend. There will
possibly be an upper level low moving over the region on Saturday,
which may help to keep temperatures slightly cooler on what would
otherwise likely be the warmest day for the next week. If
temperatures are not hindered by this, then there will likely be
some locations getting anywhere from 10 to 20 degrees above the
seasonal average for this time of year. By Sunday, the next
longwave trough is going to slowly propagate towards the region.
This will allow for there to be a cooling trend through the early
to mid part of next week, and possibly bring back a chance of
rain. Having said that, this is still quite far out in the
forecast period and thus subject to change.

(Previous discussion submitted at 156 PM):

Water vapor satellite imagery shows an upper level low currently
over western Arizona, with wrap-around moisture allowing a few light
showers to continue over the southeastern portions of California.
Instability on the back half of the low is fairly limited in our
region, with the more broad swath further east over the deserts
along the CA/NV border, but a few thunderstorms were able to develop
this morning along the desert slopes of the San Bernardino and
Riverside Mountains. At this point, the better activity has shifted
further east through Riverside County and is moving down into
Imperial County where activity will likely continue through tonight.
The thunderstorm threat will still exist through early evening for
the Riverside and San Bernardino Mountains, with gusty and erratic
winds possible, but at this point given the location of the low and
the trend of the precipitation shifting eastward already, chances
are dwindling for additional precipitation over a 0.25" outside of a
rouge thunderstorm.

Quite a few spots did fairly well over the past several days
regarding rainfall, with the San Bernardino Mountains and High
Desert the big winners. Precipitation totals were around 0.50" for
the HD and over an inch for the SB Mountains, but even some
precipitation bands that moved across the Inland Empire yesterday
and this morning helped generate around 0.35"-0.45" of rain. Areas
along the coast received some as well, although amounts were below
0.20" over the past 24 hours. Regardless, after such a dry start to
the water year, any precipitation is very welcome.

As the low moves up and out late today and tonight, precipitation
will quickly end and drier conditions settle in. Some AM marine
layer drizzle is expected along the coasts early Tuesday morning
with the deepening layer, as well as patchy fog for areas further
inland. Regarding the upper level pattern, models continue to push a
solution of a new low shifting down from Idaho on Tuesday, sweeping
across far southeastern California Tuesday evening. While previous
runs have indicated some light showers may develop as this low
pushes across, latest trends have moved the low closer to AZ,
somewhat dry slotting us on any precipitation with this next system.
At this point, have completely pulled out any precipitation chances
from the forecast beyond tonight, and dry conditions look to
prevail. Cooler temperatures will continue through Tuesday with the
cloud cover, with highs generally in the 50s in the mountains, 60s
to very low 70s along the coasts and valleys, and 80s for the
deserts.

Wednesday and beyond, a warming trend sets in with upper level
ridging building over the area. Highs quickly reach near normal by
Wednesday, and 10-20 degrees above normal by Saturday when
temperatures encroach on the mid to upper 90s for the Inland Empire
and 105 in the Coachella Valley. Even along the coast, temperatures
may reach the mid to upper 70s, fairly warm for early to mid May.
Models diverge with the pattern beyond Saturday, but current
indications point to a quick cool down for early next week with a
large upper level low moving down from OR/WA.

&&

.AVIATION...
060330..Coasts/Valleys/Coastal Slopes...BKN-OVC cloud layers between
2000-4000 feet with tops to 5000 ft cover the coastal basin,
bringing widespread terrain obscurations in FG. Bases will likely
lower slightly overnight to about 2000-3500 ft MSL. Clouds will
partially scatter out 17-20Z, with areas of BKN cigs lingering all
day, especially near the foothills. Low clouds at 1500-2500 ft MSL
will refill into most of the coastal basin after 00Z Wed.

Desert Mtn Slopes/Deserts...Isold SHRA in the high desert possible
through about 06Z, otherwise skies gradually clearing after 06Z.

&&

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

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.

&&

$$

UPDATE...Stewey
PUBLIC...Zuber
AVIATION/MARINE...CSP