Area Forecast Discussion
Issued by NWS San Diego, CA
FXUS66 KSGX 251652
Area Forecast Discussion
National Weather Service San Diego CA
950 AM PDT Tue Apr 25 2017
A trough moving inland today will be replaced by higher pressure for
warmer days Wednesday and Thursday. Mountain and desert winds will
be lighter and the marine layer will be shallower. A low pressure
system moving across the Great Basin will bring minor cooling Friday
and Saturday along with gusty northwest winds to the mountains and
deserts. Warmer again Sunday and Monday with high pressure aloft off
the California coast.
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
The marine layer deepened to around 5000 feet last night, and a weak
trough generated just enough lift to generate a few light showers
this morning. Most of the precip fell across San Diego County with
0.01" reported at Julian, Bonita, Campo, Mission Valley, San Diego
and Fallbrook. The statocu deck will mix out this morning, but
scattered to broken clouds will linger into the afternoon due to the
deep marine layer. The cloud coverage will be greatest over San
A vort max and associated speed max on the west side of a 546 dm low
in Wyoming will race across Nevada this morning and into northern AZ
this afternoon. Gusty NW winds will affect the mountains and deserts
again today, but they won`t be quite as strong as yesterday.
The trough slides farther east tonight and an expansive eastern
Pacific ridge will edge close enough to bring warmer days and
lighter winds Wednesday and Thursday. The marine layer will be a
little shallower, and night and morning coastal low clouds will be
*From Previous Discussion*
Another trough of low pressure moving through the
Great Basin will bring slight cooling for Friday and Saturday with
gusty north to northwest winds for the mountains and deserts. High
pressure aloft off the California coast will bring weaker winds and
warming for Sunday and Monday with high temperatures warming to 5 to
10 degrees above average.
251529Z...Coast/Valleys/Coastal Mountain Slopes...SCT-BKN clouds in
the 1500-5000 ft msl layer with local vis 3-5 sm and portions of the
coastal mountain slopes obscured in clouds, will likely become FEW-
SCT 2000-4000 ft msl through 26/0000 UTC with SCT clouds AOA 20000
ft msl. 26/0000-1500 UTC...patchy BKN clouds likely developing 25-35
sm inland, with bases 1500 ft msl and tops around 2000-2500 ft msl.
Mountain Ridges/Desert Slopes/Deserts...SCT clouds AOA 20000 ft msl
and P6SM vis through Wednesday morning. Westerly winds 15-25 kt with
gusts to 35 kt will produce mod-strong UDDFS and LLWS over and east
of the mountains this morning.
Strong northwest winds, with gusts 25-30 kt, and high combined seas
of 9-12 ft, will continue through this evening in the coastal waters
from 20 to 60 nm offshore. A Small Craft Advisory is in effect
through 10 pm tonight. Winds and seas will diminish late tonight and
Northwest winds and seas will increase again Thursday afternoon
through Friday, with a return of Small Craft Advisory conditions
likely for the outer waters, and maybe the inner waters for a brief
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
PZ...Small Craft Advisory until 10 PM PDT this evening for Coastal
Waters from San Mateo Point to the Mexican Border and out
to 30 nm-Waters from San Mateo point to the Mexican Border
Extending 30 to 60 nm out including San Clemente Island.