Expires:No;;026359
FXUS66 KSGX 061106
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
406 AM PDT Thu Oct 6 2022

.SYNOPSIS... 
Slow warming will continue for the coast and valleys into Saturday
followed by a cooling trend into the middle of next week while the
mountains and deserts will begin to slowly cool on Friday.
Isolated showers or thunderstorms are possible for the mountains
for this afternoon. An upper level low pressure system centered 
near northwest Mexico will spread moisture across the area with a 
slight chance for showers and thunderstorms each afternoon for 
Saturday through Monday, mainly in the mountains. Low pressure
over the western states could bring cooler and breezy conditions
around the middle of next week.

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

.SHORT TERM (Today through Saturday)...
A weak coastal eddy has developed and the marine layer has
deepened to around 2000 feet with satellite imagery showing
coastal low clouds covering much of the San Diego County valleys
and spreading into southern and western portions of the Inland
Empire. With the deeper marine layer and with cloud bases lower,
the depth of moisture is greater and there could be some patchy
drizzle into this morning. The marine layer is expected to become
slightly shallower with coastal low clouds not spreading as far 
into the valleys for tonight and Friday night.

Mid level moisture remains with continuing afternoon clouds over
the mountains. The HRRR and local NAM-bounded WRF both show
isolated showers or thunderstorms for this afternoon, mainly over
the San Diego County mountains and inland valleys. The WRF also 
develops periods of elevated convection from late Friday into 
Saturday evening with chances greater over San Diego County and 
decreasing to the northwest with chances for measurable rainfall 
greatest in the mountains. 

High temperatures for the coast and valleys may warm slowly into
Saturday while the deserts into the mountains begin to cool slowly
on Friday. 

&&

.LONG TERM (Sunday through Wednesday)...
Upper level low pressure centered over northwest Mexico will
continue to spread moisture across the area from the east and 
northeast into Monday with chances for mainly afternoon 
showers and thunderstorms with chances greatest in the mountains 
and on Sunday. 

For the middle and latter part of next week, upper level low
pressure over the West will bring some cooling. While the global
models are in closer agreement with the placement of high pressure
over the eastern Pacific, there remain greater differences with
downstream low pressure over the western states. NBM has Wednesday
and Thursday as the coolest days, depending on location, along 
with the greatest spread in the high temperature guidance. There 
are at least small chances for mostly light precipitation with 
greatest chances in the mountains. 

&&

.AVIATION... 
060930Z...Coast/Valleys...Clouds cover most of the coastal basin 
this morning. Bases vary from 700-1200 feet MSL with tops 2200 feet. 
Vis reduced 0-5SM between those elevations. Scatter out 16Z inland, 
20Z toward the coast, but clouds should persist along coast in San 
Diego County. Clouds to push ashore after 00Z and inland overnight 
into Friday, but not as far inland.

Mountains/Deserts...SCT-BKN cumulus clouds 10000 feet MSL mostly 
over the mountains 19-01Z, with isold TSRA pushing tops to 35000 
feet MSL. Local strong up/downdrafts and gusty, erratic winds near 
any TSRA. Otherwise, mostly clear.

&&

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

&&

.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...MM