San Luis Rey, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

798
FXUS66 KSGX 062059
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
159 PM PDT Tue May 6 2025

.SYNOPSIS...
Slight chance of showers for the High Desert and San Bernardino
mountains this afternoon and evening, with any precipitation
expected to move out of the region by midnight. A dry and warming
trend sets in Wednesday and beyond with the marine layer becoming
shallower. High temperatures on Saturday will be 10 to 20 degrees
above average for inland areas. For Sunday through Tuesday, a low
pressure system moving along the California coast brings a
cooling trend with night and morning coastal low clouds spreading
farther inland and onto the lower coastal slopes of the mountains
by Monday or Tuesday.

&&

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

Visible satellite currently shows a developing cu field over the
High Desert and mountains, expanding as an upper level low swings
down from Nevada. Some precipitation is expected this afternoon as
this low propagates down, but with the greatest instability well to
the east of the region, only rain showers are expected with the
thunderstorm threat expected to remain out of the area. Latest
hi-res guidance has started showing some heavier rain rates for
this afternoon and evening across the High Desert, up to
0.25-0.35"/hr, with bodes well with PW values up to 0.80-1.00".
The rain generally will reach from Running Springs eastward, with
the heavier bands expected to be on the desert foothills of San
Bernardino County. Total rainfall amounts are expected to be
light, mostly below 0.10", but some heavier rain bands could
result in amounts up to 0.40" through late tonight. Any and all
precipitation should be out of the area by midnight.

The marine layer remains deep into Wednesday morning with fairly far
inland spread, but drier air near the surface may limit any drizzle
potential for Wednesday morning along the coast. By the afternoon,
the aforementioned low will be moving into eastern Arizona and New
Mexico with upper level ridging building overhead. Heights continue
to increase through the weekend, with temperatures 3 to 10 degrees
above normal by Thursday and 10 to 20+ degrees above normal by
Saturday. Saturday may be the hottest day of the year thus far, with
highs 105-110 for the low deserts and Coachella Valley, 97-101+ for
the Inland Empire, 90s for the valleys and High Desert, 80s for the
mountains, and upper 70s to mid 80s along the coast. Spread on the
models for the high temperatures is very small, with the 25th
percentile to 75th percentile within 2-3 degrees, indicating high
confidence in this heat. With decent consensus on the warm up,
future forecast packages may need to include Heat Advisories for
some of the hotter locations, somewhat unusual for early to mid
May.

The thermal ridge axis shifts slightly eastward on Sunday to set up
over Arizona, but highs on Sunday look to remain well-above normal,
potentially only 3-7 degrees below Saturday`s highs. The pattern
changes significantly by Monday as the next system, a large upper
level low off the coast of OR pushes down, and heights fall
quickly into mid week. Any associated precipitation with this next
system remains to be seen, but cooler weather should return as
early as Monday with highs falling to near normal, and continue
cooling into mid week.

&&

.AVIATION...
062045..Coasts/Valleys/Coastal Slopes...BKN-OVC cloud layers between
2000-3500ft MSL with tops to 5000ft remaining in place across the
coastal basin this afternoon, with localized SCT across extreme
southern San Diego County and a few other portions of the coast. VIS
restrictions limited to coastal foothill obscurations in FG. Low
clouds at 1500-2500 ft MSL remain in place across the coastal basin
tonight. Expecting full scattering tomorrow afternoon by 18z
Wednesday.

Desert Mtn Slopes/Deserts...FEW-SCT cumulus clouds based near 6000-
10,000ft AGL present across the mountains and deserts this afternoon
with areas of -SHRA possible this afternoon in the high deserts of
San Bernardino County. Winds gusting 30-35kts on mountain peaks and
through passes this afternoon/evening.

&&

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

&&

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

&&

$$

PUBLIC...Zuber
AVIATION/MARINE...Munyan