Fallbrook, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

632
FXUS66 KSGX 030414
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
914 PM PDT Mon Jun 2 2025

.SYNOPSIS...

An area of low pressure will cross over the area Tuesday into
Wednesday, giving a chance of showers and thunderstorms across the
area. The best chance for these will be across the mountains, but
some storms could make their way into the western valleys and
coastal areas by Tuesday night. After the system departs, drier
and warmer weather will occur across our area as weak high
pressure moves into SoCal.

&&

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

Update: The disturbance affecting us the past weekend is now located
over the Four Corners region, and this is continuing to propagate
eastward. Some of the residual moisture on the backside of this
system has moved in over the high deserts within our CWA. Meanwhile,
there is a secondary U/L low embedded within the overall longwave
trough over the western states which is currently located over the
Pacific Ocean, nearly 200 miles WSW of Point Conception. This will
drop southward , and by tomorrow, the combination of the residual
moisture and the instability provided by the U/L low will help to
trigger the development of scattered showers and thunderstorms
tomorrow afternoon across the region. The latest high res guidance
puts the most probable location of seeing thunderstorms develop
initially will be over the San Bernardino Mountains, and then these
will likely drift to the south into the IE by later in the
afternoon, and then continue to move over the mountains of San Diego
County by later in the evening. Some of these storms will be capable
of producing brief periods of heavy rain, strong and gusty winds,
and dangerous lightning. There will even be the chance of a storm or
two during the overnight hours tomorrow night and going into the
early morning hours on Wednesday.

By Wednesday, the U/L low will continue to weaken and move east, and
although there will still be some showers and thunderstorms
possible, the coverage of this will likely not be as widespread as
Tuesday and more confined to just the mountains and deserts. Having
said that, a stray shower and/or thunderstorm will still be possible
over the coastal and inland areas. Some of the high res models, such
as the HRRR, show a much drier solution. From there on, not much has
changed within the long term portion of the forecast.

(Previous discussion submitted at 125 PM):

A 575 mb low west of Point Conception will continue to push
southeast across the California Bight through tonight. As the
system moves closer to our region by Tuesday and Wednesday, the
chance for showers and thunderstorms will increase, notably
across the mountains.

Southeasterly and easterly flow aloft accompanied by adequate
subtropical moisture and instability will move over the area as
this system comes into the area. NBM thunder probabilities go up
to 20-30 percent across parts of the Inland Empire, northern
mountains and deserts. These storms could arrive by Tuesday
afternoon but more likely by the evening hours and overnight. As
the moisture wraps around the low, cloud to ground lightning,
heavy rain and small hail are possible as these form over the
mts/deserts in the evening and push westward into the valleys.
Confidence lowers with the forecast for storms at the immediate
coast, with the best chance to see these sometime Tuesday night.
Some areas will receive nothing, others could receive near one
half inch or locally more. As the low pushes further inland into
the desert, the backside of it may leave some light showers over
the area on Wednesday morning. With instability and moisture still
readily available, hi-res models continue to show the potential
for more storms to fire mainly in the mountains and high desert by
Wednesday afternoon. These storms may produce higher hourly rates
than Tuesday, but confidence on this is low. High temperatures
will remain relatively unchanged through this period with
lingering humidity.

As the system departs by Thursday, drying will occur across the
region (hello, less humidity!) with a subtle warming trend
beginning. The marine layer will rebuild itself as well, with
night and morning low clouds near the coast. Model ensemble
guidance is in fair agreement of a weak trough remaining over the
area keeping temperatures from getting too warm, with a high
pressure system slowly building into the area thereafter. This
system will bring in more warmer weather by the weekend into early
next week.

&&

.AVIATION...
030400Z....Coasts/Valleys...Low clouds based at around 900-1300ft
MSL have filled in about 15-20 miles inland across San Diego County
this evening, and will continue to slowly fill in through Orange
County over the next hour or so. Expecting clouds to continue to
spread into the Inland Empire overnight, brining CIGs to KONT and
KSBD by 10-12z. VIS reductions possible down to 3SM or less in the
inland valleys (including the Inland Empire) and where clouds
intersect higher terrain. Clearing will occur generally from east to
west in the morning, with most inland areas clearing by 17z, with
clearing to the coast occurring by 19-20z. 30-40% chance that low
clouds remain over coastal San Diego County (I-15 westward) through
Tuesday afternoon and around a 10% chance for coastal Orange County.
Clouds surge back inland after 00z initially across San Diego
County, eventually spreading northward into Orange County and the
Inland Empire, with similar coverage/timing and cloud bases as this
evening.

.Mountains/Deserts...VFR prevails and mostly clear skies through
Tuesday afternoon. A stray shower or thunderstorm is possible over
the mountains Tuesday afternoon, primarily after 20z and across the
San Bernardino Mountains. Locally gusty and erratic winds near any
thunderstorms that develop.

&&

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

&&

.BEACHES...
A long period south swell will bring elevated surf up to 6 feet
primarily for south and southwest facing beaches through Tuesday
resulting in a higher rip current risk and locally hazardous
swimming conditions. A Beach Hazard Statement remains in effect and
contains more information.

&&

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

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through Tuesday afternoon for Orange
     County Coastal Areas-San Diego County Coastal Areas.

PZ...None.

&&

$$

UPDATE...Stewey
PUBLIC...APR
AVIATION/MARINE/BEACHES...Munyan