147
FXUS66 KSGX 111635
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
935 AM PDT Sun Aug 11 2024

.SYNOPSIS...
Slightly cooler today with continued chances of thunderstorms
over the mountains and deserts. Lower thunderstorm chances on
Monday with any activity limited to the mountains and southern
deserts. Drier with near normal temperatures Tuesday through the
end of the week. Patchy low clouds and fog will gradually increase
for the coastal areas each night and morning.

&&

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

Coastal low clouds never made their presence felt over land this
morning, probably discouraged by the easterly flow aloft from our
inverted trough aloft. This trough continues to bring in
monsoonal moisture today and chances of thunderstorms for
mountains and deserts. It looks quite unstable and humid, so we
should get at least several decent storms this afternoon and early
evening. Any storm would produce frequent lightning and could
produce flash flooding and strong, gusty winds. Elsewhere it
should be mostly sunny with a hampered marine layer. A coastal
eddy today should help repair the marine layer, so coastal low
clouds should make an earlier comeback late today and tonight.
Temperatures will start to moderate today from those highs
yesterday. The potential temp rise is literally dampened by the
low level moisture intrusion this morning. So not so hot, but more
muggy. The inverted trough overhead today will fade as a low
pressure trough off the Pac northwest coast will amplify over the
next couple days. This will effectively sweep away the monsoonal
moisture, but enough residual moisture and instability remain
over southeastern mountain/desert portions of our area for a
slight chance of tstorms Monday afternoon. The amplifying trough
to the north will help rebuild the marine layer and boost winds
through mountain gaps into deserts during the afternoons and
evenings. Temps will settle down to around normal. Coastal clouds
will become more uniform, extensive and longer lasting, but still
restrained to nights and mornings. Expect these seasonal and dry
conditions to remain with very little day to day variation this
entire week.

&&

.AVIATION...
111530Z...Coast/Valleys...Mostly clear skies with some FEW-SCT
clouds near 20K ft MSL. Low clouds based near 700-1100 ft MSL
offshore with tops near 1200 FT MSL locally impacting coastal areas
with local VIS 3-5 miles. ISO TSRA drifting into foothills and
adjacent valleys west of the mountains this afternoon with the
highest chance in SD County.

Low cloud coverage confidence higher (50-70%) in cigs reaching
coastal TAF sites later tonight, mainly after 06Z Mon based near
1000 ft MSL with tops to near 1500 ft MSL.

Mountains/Deserts...SCT-BKN clouds with bases around 10,000 ft MSL
develop after 16Z, followed by scattered TSRA between 19Z Sunday and
03Z Monday. Gusty and erratic winds possible near storms as well as
MOD UDDFS.

&&

.MARINE...
No hazardous marine conditions are expected through 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...MM
AVIATION/MARINE...Small