Arrowhead Highlands, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

895
FXUS66 KSGX 111838
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
1138 AM PDT Sat Apr 11 2026

.SYNOPSIS...
Low pressure systems will impact the region through Monday. These
are going to be accompanied by cooler, wetter. amd windier
weather. A chance for light showers will occur tonight into
Saturday morning. These weather systems will also bring the chance
of light to moderate rainfall and high elevation snow. The
heaviest rainfall and mountain snowfall is expected on Sunday,
where there is a slight chance of thunderstorms west of the
mountains. This low pressure system may linger over the area into
Monday, bringing additional light showers. Drier and slightly
warmer weather is expected by the middle and end of next week.

&&

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

Precipitation...

Light and intermittent rain showers across the coastal basin this
morning on the heels of a weak front that moved through, with
drier conditions for the remainder of the day as a large upper
level low moves into Northern California. Heights continue to fall
both today and tomorrow with 850mb temps dropping to around 5C by
Sunday, ushering in surface high temps in the mid-60s for most
locations, and 30s-40s for the mountains. Ample mid and low level
moisture will translate to light to moderate rain showers early
Sunday morning as a cold front pushes through, with rain rates
around 0.2-0.4"/hr, locally higher for the mountains. The front
looks to arrive around sunrise on Sunday for Orange and San
Bernardino counties, moving southward throughout the day with the
heaviest rain expected late morning into early afternoon. While
the threat is low, there remains a chance for thunderstorms
associated with the frontal passage on Sunday, primarily late
Sunday morning into early afternoon. Should storms develop, brief
but heavy rainfall with rain rates exceeding 0.50"/hr will be
possible. Snow levels will be falling throughout the weekend, from
around 6500 ft today closer to 5000-5500 ft Sunday afternoon.
Elevations above 6000 ft may see light accumulating snow on
Sunday. The coldest point of the system will be occurring as the
rain tappers off, so snow accumulations will likely be 1" or less
for populous areas. Rain chances decrease on the backside of the
front by early Monday, although a shortwave embedded in the deeper
low will quickly move through Monday afternoon before the system
departs. With this shortwave, additional rain/snow in San Diego
County and up along the spine of the mountains to the San
Bernardino Mountains will be possible Monday afternoon and
evening, but the lower levels will be quickly drying out and
little in the way of precipitation is expected.

Ultimately, rain totals will be low with this event, likely at or
below 0.50" for the coastal basin and inland areas, less than 0.25"
for the immediate coast, and around 0.50-1.00" for the mountains.
Higher elevations will perform better where upslope flow may
assist in thunderstorm development on Sunday, allowing for spots
of higher rain amounts.

Winds...

Increasing winds today and tonight with the tightening gradient as
the low approaches, providing sustained surface winds 35+ mph and
gusts as high as 55 mph through mountain passes and on the desert
slopes of the mountains. Closer to mountain peaks, even stronger
winds may make for dangerous conditions for low-flying aircraft
and an increase in turbulence. While models project the strongest
winds with this system to begin after 1 PM today and last through
midnight/2 AM Sunday, the push of this cold front may maintain
stronger wind gusts into Sunday afternoon, with no significant
drop off between 2 AM and sunrise. Along with the gusty winds,
blowing dust through the High Desert and Coachella Valley will be
a threat today through Monday, before winds settle a bit on
Tuesday.

Beyond Monday...

Increasing heights and drier air will settle in by Tuesday, with
northwest flow and lighter winds. Weak upper level ridging attempts
to build in and temperatures should rebound closer to near normal
for mid April by Wednesday. A late week pattern change could
potentially bring additional rainfall, although there are equal
chances for an inside slider to bring about strong offshore winds.
Currently, the forecast remains dry into next weekend with high
temperatures increasing each day, but should this system be able
to swing further south than currently projected, another rainy
weekend may be in store. For now, plan on dry and warm with highs
returning to the 80s for many inland areas, and gustier offshore
winds.

&&

.AVIATION...
111800Z...Coasts/Valleys...Precipitation from this morning has
cleared out, with FEW-SCT cumulus (based around 2000-3000ft MSL)
draped across the coastal basin for this morning into the afternoon.
VFR prevails through this evening with the next disturbance bringing
the return of largely BKN clouds around 3500ft MSL, set to fill
back in across the coastal basin starting after 02z Sunday. Very
scattered -SHRA become possible around 12z, though a more defined
band of precipitation will move from NW to SE from 14-22z Sunday
morning. This band of rainfall will bring MVFR CIGs near 2000ft MSL,
with VIS 4-6SM in -RA/BR. Pockets of heavier rainfall could bring
CIGs below 1000ft with VIS closer to 2-4SM.

.Mountains/Deserts...West to southwest winds pick up after 19Z
today, with gusts 35-50 kt through passes, along deserts slopes and
locally into the deserts. Local areas BLDU (vis 3-5SM) expected.
Moderate up/downdrafts in lee of mtns. Winds decrease by about 10-15
kts after 06z, but remains elevated into the overnight hours,
picking back up by 18-21z Sunday.

&&

.MARINE...
There is a slight (~10%) chance of thunderstorms Sunday afternoon.
Additionally there will be periods of increased northwest winds with
gusts 15 to 20 kt and choppy seas through the day Sunday.

&&

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

&&

$$

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