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000 
FXUS66 KSGX 111026
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
226 AM PST Wed Dec 11 2019

.SYNOPSIS...
Building high pressure will bring dry, mild weather through
Friday. Thursday and Friday will be the warmest days. A weak 
trough moving over Southern California this weekend will bring 
cooler weather along with gusty winds in the mountains and 
deserts. Offshore flow and higher pressure will bring some 
northeast winds Monday and a warming trend.

&&

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

High clouds are exiting stage right this morning as patchy low
clouds appear and disappear intermittently near the coast. We are
looking at fair weather this upcoming week, but with a variety of
trends in clouds and breezes. A weak shortwave trough moving 
through the state this morning will be followed by a high pressure
ridge over California. That will warm our air mass some, enough 
to boost high temperatures 5-10 degrees above average Thursday and
Friday. A mix of patchy high and patchy low clouds will continue.
The jet stream drops southward this weekend, breaking down the 
ridge and energizing the westerly onshore flow. It will be much 
cooler this weekend as a result. Increased humidity will generate 
some clouds from the coast to the mountains. There are hints of 
very light precipitation Saturday evening, but not enough to 
forecast showers yet. The main impact from this trough will be 
strong winds in the mountains and deserts with gusts that could 
peak over 50 mph in spots. Some offshore flow gets started Sunday 
and peaks Monday morning, but recent guidance has dialed back the 
strength of offshore winds. Current estimates are for top gusts 
reaching around 35 mph in the wind- prone foothills. High pressure
aloft builds a bit, making for a modest warming trend next week 
with high temps inching above average. After a dry nine days or 
so, there is some guidance showing the next Pacific trough drawing
moisture from the southwest for precipitation next Wednesday or 
Thursday, but there is little model consensus or consistency in 
that solution.

&&

.AVIATION... 
110945Z...Coastal areas...SCT-BKN low clouds at times through 16Z 
with bases 700-1000 ft MSL. Any cigs at coastal airports will be 
brief.

Otherwise, SCT-BKN clouds above 20000 ft MSL through Wed night with 
mostly unrestricted vis.

&&

.MARINE... 
No hazardous marine weather is expected through Thursday. A large, 
long period west-northwest swell will create combined seas of 8 to 
11 ft Friday through Sunday. This could create hazardous boating 
conditions. West-northwest winds will increase over the outer 
coastal waters Saturday through Sunday with gusts of 25 kt possible. 

&&

.BEACHES...
A west northwest swell with a period of 16-17 seconds will bring 
elevated to high surf and strong rip currents to the beaches Friday 
through Sunday. Current projections are for 5-7 foot surf with local 
sets to 8 feet, especially in southern San Diego County. Swell 
periods are likely to be in the 16-17 second range. A Beach Hazards 
Statement is in effect from 10 AM Friday through 4 PM Sunday.

&&

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

&&

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

PZ...NONE.

&&

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