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000 
FXUS66 KSGX 230518
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
918 PM PST Tue Jan 22 2019

.SYNOPSIS...
Into next week, high pressure aloft will be centered near the West
Coast with a broad trough of low pressure covering much of the
rest of the lower 48 states. Lower level flow will be mostly
offshore with gusty northeast winds along and near the coastal
mountain slopes and below passes and canyons. There will be
periods of stronger Santa Ana Winds, one through Wednesday
morning, another early Friday morning through Saturday, then 
yet another on Tuesday. High temperatures will warm into 
Saturday, then may cool a little by the middle of next week.

&&

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

...Update...

Santa Ana Winds continued but not widespread. Freemont Canyon
gusting to 53 mph this evening, Pavika Ridge 46 mph and 38 mph at
Rialto. The offshore pressure gradients have only decreased 1 mb
between San Diego and Tonapah. This gradient though will continue
to relax through Wednesday, allowing the offshore winds to relax.

An upper level ridge will dominate the weather across California
through the weekend and into early next week. This will maintain
dry weather conditions along with warming temperatures. Bouts of
similar strength Santa Ana Winds are expected - one occurring now
through Wed morning, another early Friday morning-Saturday, and
yet another on Tuesday. 

Any chances of rain and mountain snow returning? There are signs
as we enter into February that the West Coast ridge will begin
breaking down. This would favor higher rain and mountain snow
chances for northern and central California. For Southern
California, it remains to be seen if the ridge will continue to
hold Pacific storms systems off to our north of if we might
transition back to a wet pattern. 

...Previous Discussion (Issued at 148 PM PST Tue Jan 22 2019)...

At 1 PM, water vapor satellite showed an upper-level ridge off of
the CA coast, with northerly flow over southern CA. A 1035 mb 
surface high over northern Nevada and a 1020 mb surface low over
northern Baja was creating east to northeast surface gusts of 
35-45 mph through mountain passes and along coastal mountain 
slopes into the foothills, with isolated gusts near 55 mph. A 
Wind Advisory remains in effect for the mountains, valleys and San
Gorgonio Pass through noon, Wednesday with weaker winds expected 
overnight and Wednesday morning. 

The ridge will build east tomorrow closer to CA. This, combined
with the downsloping east to northeast winds, will help high
temperatures soar to 5-10 degrees above normal Wednesday. The
above normal highs will continue through early next week as the
upper-level ridge remains to our west and periods of offshore flow
develop with troughs moving over the Great Basin. With this
pattern, night/morning low clouds will be scarce along the coast.
The next round of gusty east to northeast winds will be Thursday
night though Saturday, with strongest winds possibly Saturday
morning, then another round is expected Monday morning into
Tuesday.

&&

.AVIATION... 
230430Z...Coast/Valleys/Mountains...Clear with unrestricted vis 
through Wednesday. Gusty winds to continue this evening, with gusts 
to 20 kt possible at KONT and KSNA. Winds to gradually diminish 
overnight. Pockets of UDDFS and LLWS possible over and SW of 
mountains through tonight.

Deserts...Clear with unrestricted vis through Wednesday. Prevailing 
N/NW winds with occasional gusts to 15 kt through this evening. 
Pockets of UDDFS and LLWS possible.

&&

.MARINE... 
No hazardous marine weather expected through Saturday.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory until noon PST Wednesday for Orange County Inland 
     Areas-Riverside County Mountains-San Bernardino County 
     Mountains-San Bernardino and Riverside County Valleys-The 
     Inland Empire-San Diego County Mountains-San Diego County 
     Valleys-San Gorgonio Pass Near Banning-Santa Ana Mountains 
     and Foothills.

PZ...NONE.
&&

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