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Area Forecast Discussion
National Weather Service San Diego CA
430 AM PST Tue Dec 6 2016

.SYNOPSIS...
A low pressure system moving from the Pacific Northwest into the
Great Basin will bring stronger onshore flow across Southern
California through tonight with more clouds and with gusty west
winds in the mountains and deserts. Weak offshore flow will follow
for Wednesday into Thursday bringing warming on Thursday and gusty
northeast winds below the Cajon Pass and for the coastal foothills
of the Santa Ana Mountains Wednesday. A little cooler into
Saturday...then a little warmer into early next week with periods
of high clouds at times.

&&

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

.SHORT TERM (Today through Thursday)...
A low pressure system moving from the Pacific Northwest into the
Great Basin will bring stronger onshore flow across Southern
California with periods of stronger and gusty west winds for the
mountains and deserts from late this morning through late tonight.
It will also bring deepening of the marine layer with low clouds
extending on the coastal mountain slopes. There could be a few
sprinkles or light showers...mainly late this afternoon through
this evening...near the coastal mountain slopes into adjacent
portions of the Inland Empire.

Offshore flow will follow for Wednesday...with weaker offshore
flow for Wednesday night into Thursday. Winds could be near
advisory strength below the Cajon Pass and into the coastal
foothills of the Santa Ana Mountains for Wednesday morning into
early Wednesday afternoon. High temperatures will be near to
around 5 degrees below average for today and Wednesday...warming
to near to around 5 degrees above average for Thursday.

Besides the coastal low clouds that will continue into Wednesday
morning...there will continue to be high clouds at times through
Thursday.

&&

.LONG TERM (Friday through Monday)...
Generally zonal flow will continue into next week across the
eastern Pacific into the western states with the subtropical jet
axis remaining to the north of Southern California. A weak
shortwave moving inland through the Great Basin on Saturday will
bring stronger onshore flow with gusty west winds in the
mountains and deserts...cooling to slightly below average...and a
return of the marine layer with night and morning coastal low
clouds and fog. Warming for Sunday and Monday with weaker onshore
flow. With Southern California remaining just south of the
subtropical jet axis...there will continue to be periods of high
clouds.

&&

.AVIATION... 
061000Z...Coast/Valleys...Low clouds filling the coastal basin will
only partially clear today. Bases will be around 3000 feet msl and
vis reduced between 3000-4000 feet msl where these clouds touch the
terrain. Some areas will scatter out, but it will be random and most
likely between 18-00Z this afternoon. Mountains/deserts...areas of
strong westerly winds this afternoon and evening causing lee waves,
moderate up/down drafts and pockets of llws. Otherwise, variable
high clouds today and tonight.

&&

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

&&

.FIRE WEATHER...
Offshore flow will develop on Wednesday bringing gusty northeast
winds and lower humidities below the Cajon Pass and for the
coastal foothills of the Santa Ana Mountains with elevated fire
weather conditions from mid morning through early afternoon
Wednesday. Weaker winds winds with lower humidities for the
valleys on Thursday.

&&

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

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory from 10 AM this morning to 3 AM PST Wednesday for 
     Apple and Lucerne Valleys-Riverside County Mountains-San 
     Bernardino County Mountains-San Diego County Deserts-San 
     Diego County Mountains-San Gorgonio Pass Near Banning.

PZ...None.

&&

$$

PUBLIC/FIRE WEATHER...17
AVIATION/MARINE...MM

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