064
FXUS66 KSGX 290542
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
942 PM PST FRI NOV 28 2025
SYNOPSIS
RELATIVELY QUIET WEATHER EXPECTED THROUGH EARLY NEXT WEEK WITH
WEAK OFFSHORE WINDS SATURDAY AND AGAIN MONDAY. NIGHT AND MORNING
COASTAL LOW CLOUDS AND FOG WILL INCREASE IN COVERAGE AND SPREADING
A LITTLE FARTHER INLAND EACH NIGHT THROUGH THE WEEKEND. NEXT
POTENTIAL STORM SYSTEM WILL OCCUR WEDNESDAY INTO THURSDAY, BUT
CONFIDENCE IN RAINFALL CONTINUES TO BE LOW, WITH INCREASING
CHANCES CHANCES FOR DRY WEATHER AND YET ANOTHER ROUND OF OFFSHORE
FLOW MID WEEK.
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
THIS EVENING, THE MARINE LAYER REMAINS QUITE SHALLOW IN SPITE OF
THE TROUGHING/CYCLONIC FLOW AND LOWER HEIGHTS ALOFT. THE LOW
CLOUDS HAVE INCREASED IN COVERAGE FROM THIS TIME LAST NIGHT AND
HIGH RESOLUTION MODELS EXPECT THAT TREND TO CONTINUE, WITH LOW
CLOUDS AND FOG SPREADING A LITTLE FARTHER INLAND. SFC PRESSURE
GRADIENTS ARE WEAK BUT TRENDING ONSHORE. TODAY HIGH TEMPERATURES,
ESPECIALLY IN THE COASTAL AREAS, WERE SEVERAL DEGREES LOWER THAN
YESTERDAY AFTERNOON. TODAY'S HIGH TEMP AT SAN DIEGO INTERNATIONAL
AIRPORT WAS 12 DEGREES LOWER THAN YESTERDAY.
FROM PREVIOUS DISCUSSION...
THE RIDGE THAT HAD PREVIOUSLY BEEN OVERHEAD HAS BEEN FLATTENED OUT
WITH A SHORTWAVE TROUGH MOVING FROM THE PACIFIC NORTHWEST INTO
THE GREAT BASIN THIS WEEKEND. ULTIMATELY, THE RESULT OF THIS
TROUGH WILL BE MINIMAL, WITH WEAK OFFSHORE WINDS IN THE DESERTS
AND MOUNTAIN PASSES, AND ONSHORE FLOW DOMINATING FOR THE COASTS
AND VALLEYS. THE ONSHORE FLOW AND A WEAK COASTAL EDDY TONIGHT WILL
HELP CLOUDS FILL IN BETTER, LIKELY PUSHING ASHORE OVERNIGHT, WITH
PATCHY FOG EXPECTED ALONG ELEVATED COASTAL TERRAIN AND PORTIONS
OF WESTERN VALLEYS. OTHERWISE, RELATIVELY BENIGN WEATHER EXPECTED
THROUGH THE WEEKEND WITH MOSTLY CLEAR SKIES AND TEMPERATURES
WITHIN 5 DEGREES OF SEASONAL NORMS. YET ANOTHER INSIDE SLIDER DIGS
THROUGH THE GREAT BASIN SUNDAY INTO MONDAY, REINFORCING THE
OFFSHORE GRADIENT AND LEADING TO ANOTHER ROUND OF OFFSHORE WINDS.
THIS EVENT LOOKS TO BE A TOUCH STRONGER THAN SATURDAY'S OFFSHORE
FLOW WITH EASTERLY/NORTHERLY WINDS EXTENDING INTO THE INLAND
VALLEYS, HOWEVER, THE EVENT IS STILL RATHER WEAK.
THE TIMING OF THE NEXT DISTURBANCE IS IN THE TUESDAY-WEDNESDAY
WINDOW, THOUGH A GREAT DEAL OF UNCERTAINTY REMAINS IN THE DEPTH OF
THE TROUGH, WITH REASONABLE SPREAD IN THE ENSEMBLES VARYING FROM
A TROUGH DEEP ENOUGH TO BRING SHOWERS TO THE AREA, TO A SHALLOWER
TROUGH THAT COULD BRING ANOTHER ROUND OF OFFSHORE FLOW WITH NO
PRECIPITATION. A DRIVING FACTOR IN THE EVOLUTION OF THIS TROUGH
AND IT'S FORECAST DEPTH IS A CUT-OFF LOW WELL OFF THE SOUTHERN
CALIFORNIA COAST EARLY-MID NEXT WEEK. IF THE CUT-OFF LOW STAYS
CLOSE AND INTERACTS WITH THE TROUGH, PRECIPIATION CHANCES BECOME
MORE LIKELY AND OFFSHORE FLOW WILL BE MORE LIMITED. ENSEMBLES ARE
FAIRLY SPLIT IN PRECIPITATION, WITH ABOUT A 50/50 CHANCE FOR
SHOWERS. EVEN STILL, SHOULD THE RAINY SOLUTION PAN OUT, RAINFALL
TOTALS WILL BE LIGHT, GENERALLY 0.1" OR LESS, LOCALLY UP TO 0.25"
ON THE COASTAL SLOPES. SNOW LEVELS BETWEEN 6500-7000FT, SO A FEW
FLAKES ARE POSSIBLE IN THE MOUNTAINS IF PRECIPITATION OCCURS. THE
MOST CERTAIN ASPECT OF THIS FORECAST WILL BE TEMPERATURES ABOUT 5
TO 10 DEGREES BELOW AVERAGE.
AVIATION
290400Z....COASTS/VALLEYS...LOW CLOUDS BASED 700-1100 FT MSL HAVE
DEVELOPED OFFSHORE AND LOCALLY ALONG COASTAL REGIONS. CLOUDS WILL
SPREAD THROUGH THE COAST AND INLAND TO 10-15 MILES OVERNIGHT.
LOCALIZED VIS REDUCTIONS TO 4-6 SM FOR PARTS OF THE COAST, 1-3SM FOR
ELEVATED COASTAL TERRAIN. CIGS EXPECTED TO RISE SLIGHTLY OVERNIGHT.
LOW CLOUDS CLEARING TO THE 15-17Z. LOW CLOUDS 800-1200 FT MSL
REDEVELOP AND PUSH ASHORE AFTER 30/04Z.
MOUNTAINS/DESERTS
VFR CONDITIONS EXPECTED THROUGH THE TAF
PERIOD.
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...PG
AVIATION/MARINE...CSP
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