Preview of NWS' New Version of Forecast
This preview is not operational and should not be used for support decisions.

Area Forecast Discussion (AFD)

Issued by San Diego, CA (SGX)

                            
000
FXUS66 KSGX 111053
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
253 AM PST Tue Dec 11 2018

.SYNOPSIS...
Mid and high clouds across the area early this morning will move
to the east as a weak low pressure system over the California
bight moves southeastward into Baja. High pressure aloft and weak
offshore flow will bring warming west of the mountains for 
Thursday with locally gusty northeast winds near the coastal 
slopes of the mountains. A little cooler for Friday as onshore 
flow returns, then a little warmer for next weekend under weak 
high pressure aloft.

&&

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

.SHORT TERM (Today through Thursday)...
A weak upper level low pressure system centered over the 
California bight early this morning will continue to move toward 
the southeast. The subtropical moisture that it is drawing 
northward into portions of southern California in the form of mid 
and high clouds will be pushed off to the east this morning. There
will also be some patchy low clouds and fog near the coast this 
morning. 

High temperatures will fluctuate near those of Monday for today 
and Wednesday with more patchy coastal low clouds and fog for 
tonight into Wednesday morning.

For Thursday, high pressure aloft along the West Coast and surface
high pressure over the Great Basin and central Rockies will bring
warming west of the mountains and gusty east to northeast winds
near the coastal slopes of the mountains and below passes and
canyons.

&&

.LONG TERM (Friday through Monday)...
A trough of low pressure moving inland along the West Coast on
Friday will bring a return of onshore flow with cooling for
coastal and valley areas. The return of onshore flow will also
bring a return of patchy coastal low clouds and fog for Friday 
night into Saturday morning. High temperatures will warm a few 
degrees for Saturday and Sunday with weaker onshore flow and with 
weak high pressure aloft moving inland through the western 
states.

For Sunday night into Monday, a weak low pressure system in the
southern stream of the westerlies may amplify somewhere in the
vicinity of the southwest states. If it amplifies a little to the
west of southern California, it could bring some light
precipitation to portions of southern California. It it amplifies
to the east, the passage through southern California would be
mostly dry. This brackets the range of global model solutions for
early next week in the vicinity of the southwest states with no
clear model preference yet to emerge.

&&

.AVIATION... 
111000Z...High clouds will decrease as coastal low clouds increase 
this morning. Areas of coastal cigs will be around 800-1200 feet msl 
and vis reduced to 3-5SM. Scatter out will occur by 16Z followed by 
mostly clear skies. Areas of coastal low clouds will redevelop after 
03Z tonight, but with bases closer to 1500-2000 feet msl.

&&

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

&&

.BEACHES...
Surf will create a high rip current risk today. Surf up to 6 feet is 
forecast, mainly in southern San Diego County, before subsiding 
tonight and Wednesday.

&&

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

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...17
AVIATION/MARINE/BEACHES...MM