Arrowhead Highlands, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

182
FXUS66 KSGX 161639
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
939 AM PDT Mon Sep 16 2024

.SYNOPSIS...
Cooler and windier today with isolated light showers this morning.
Dry conditions with a few degrees of warming and weaker winds are
expected Tuesday. For Wednesday evening into Thursday, unsettled
weather is expected again with additional chances of precipitation.
Drier and warmer conditions expected Friday through the weekend.

&&

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

A few isolated showers have been observed on radar as of 9 AM this
morning. Rainfall accumulations so far have been light and mostly
under 0.10 of an inch. The shower activity so far has been confined
to the higher terrain, locally along the coast and in the valleys.
The isolated shower activity is expected to diminish into the
afternoon. For early Tuesday, light showers or drizzle are possible
mainly in San Diego County but coverage will mostly be confined to
higher terrain. Periods of gusty winds are expected this afternoon
and evening. Strongest winds will be through passes and into the
deserts. Peak gusts of 35 to 45 mph are expected over the mountain
ridge tops, desert slopes, and High Desert. Gusts 45 to 55 mph are
expected in the San Diego deserts with gusts up to 65 mph possible
through the Cajon Pass.

Dry conditions are expected for much of the day Tuesday (only
exception may be Tuesday morning) into Wednesday evening. A few
degrees of warming is expected Tuesday west of the mountains and in
the low desert with 5 to 10 degrees of warming in the mountains and
High Desert. Winds will be weaker as well.

On Wednesday an upper level low will begin to dig south along the
coast of the Pacific Northwest. By Wednesday night or early Thursday
morning the low will begin to move inland across Central and
Southern California. This system is expected to bring additional
chances of precipitation to Southern California as early as late
Wednesday night. This system looks like a warmer one, so there will
only be minor fluctuations in temperatures for Tuesday through
Thursday. Current ensemble guidance does not have a very significant
uptick in winds with ensembles indicating winds may be weaker than
today. NBM chances of wind gusts greater than 45 mph are 35 to 45
percent for Wednesday and Thursday afternoon and evenings and
confined to wind prone passes, like the San Gorgonio Pass. Current
high resolution model guidance is showing the potential for rainfall
totals more than what we`re seeing today for Thursday but likely
under 0.50 inch total for most locations.

For Friday through next weekend, the low pressure system over the
southwest states will weaken and move east with high pressure over
the eastern Pacific moving across California. High temperatures will
be several degrees warmer for Friday and Saturday with high
temperatures for next Sunday warming to a few degrees above average
for the deserts to around 5 degrees above average for the coast and
valleys, mostly in the 90s for the inland valleys and 100 to 105 for
the lower deserts.

&&

.AVIATION...
161530Z...Low clouds with bases varying 2000-3500 feet MSL and tops
to 5200 feet will continue to shroud the coast to mountains,
including higher terrain obscured in BR. -RA or -DZ likely anywhere,
but most likely in foothills under these clouds through 18Z.
When/where this precip occurs, vis could be reduced 0-5SM and cigs
drop to 1500 feet MSL. Partial scatter out more likely at coast
starting at 19Z and working inland, probably not scattering out much
if at all in far inland valleys. Low clouds and fog to fill in the
entire coastal basin again tonight into Tuesday, but with bases/tops
a few hundred feet lower. Confidence in late afternoon clearing at
KSAN per the TAF is MDT-HIGH.

Smoke from the Line, Bridge and Airport fires will continue to
reduce VIS in mountains, with hazy conditions over the Inland Empire
and parts of the deserts.

West-northwest winds will gust 40-50 knots through mountain passes,
continuing into tonight. Local moderate up/downdrafts in lee (east)
of mountain ridges.

&&

.MARINE...
No hazardous marine conditions are expected through Friday.
Although, northwest gusts around 20 knots are expected in the outer
waters this afternoon and evening and again Wednesday afternoon and
evening.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory until 9 PM PDT this evening for Apple and Lucerne
     Valleys.

     Wind Advisory until midnight PDT tonight for San Diego County
     Deserts.

     Wind Advisory until midnight PDT tonight for San Gorgonio Pass
     Near Banning.

PZ...None.

&&

$$

PUBLIC...CO
AVIATION/MARINE...Small