165
FXUS66 KSGX 270938
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
238 AM PDT SUN JUL 27 2025
SYNOPSIS
A TROUGH ACROSS THE WEST COAST WILL CONTINUE COOLER THAN NORMAL
WEATHER THROUGH THE WEEKEND. HIGH PRESSURE WILL EXPAND FURTHER
WEST, BRINGING A WARMING TREND SUNDAY INTO WEDNESDAY, FOLLOWED BY
A SLIGHT COOLDOWN THROUGH FRIDAY, AND THEN TEMPERATURES STAYING
NEAR AVERAGE THROUGH THE END OF NEXT WEEKEND. BREEZY WEST WINDS
WILL CONTINUE THIS WEEKEND ACROSS MOUNTAINS AND DESERTS, WHILE THE
MARINE LAYER PROVIDES LOW CLOUDS AT TIMES WEST OF THE MOUNTAINS.
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
TODAY THROUGH WEDNESDAY...
CURRENTLY, LATEST SATELLITE IMAGERY DISPLAYS THE MARINE LAYER
CONTINUING TO FILL INTO MOST OF THE COASTAL AREAS AND THE INLAND
VALLEYS OF ORANGE AND SAN DIEGO COUNTY. THE LOW CLOUDS ARE
STRUGGLING TO MAKE IT INTO THE INLAND EMPIRE (IE), ALTHOUGH SOME OF
THESE CLOUDS WILL LIKELY PENETRATE FURTHER EAST THAN ONTARIO AND
INTO THE SOUTHERN AREAS OF THE THE IE, NAMELY IN THE
MURRIETA/TEMECULA AREA, BY LATER THIS MORNING JUST BEFORE
DAYBREAK. THERE COULD ALSO BE SOME AREAS OF PATCHY FOG AS WELL
WITHIN SOME OF THE WIND-SHELTERED VALLEYS, AND WHERE THE MARINE
LAYER INTERSECTS THE MOUNTAINS. WITH THE TROUGH UPSTREAM NORTHEAST
OF THE CWA, THERE IS STILL AN INFLUENCE ON LOWER HEIGHTS OVER THE
REGION, AS WELL AS A PERSISTENT ONSHORE FLOW, WHICH WILL CONTINUE
TO KEEP TEMPERATURES BELOW THE SEASONAL AVERAGE, ALTHOUGH IT WILL
BE SLIGHTLY WARMER FROM WHERE TEMPERATURES WERE YESTERDAY,
ESPECIALLY WITHIN THE IE, DUE TO LACK OF AM CLOUDS. THIS HAS ALSO
PROVIDED SOME GUSTY WINDS DURING THE AFTERNOON FOR THE HIGHER
TERRAIN, AS WELL AS PORTIONS OF THE LOWER DESERTS SUSCEPTIBLE TO
GUSTY WINDS. OVER THE NEXT COUPLE OF DAYS THROUGH WEDNESDAY, THERE
WILL BE A GRADUAL WARMING TREND EACH DAY AS THE RIDGE OVER THE
DESERT SOUTHWEST BUILDS SLIGHTLY, WITH THE AXIS SHIFTING A LITTLE
FURTHER WESTWARD AND TOWARDS THE REGION. THIS WILL ALSO ALLOW FOR
THE MARINE LAYER TO LOWER AND THIN MORE, AND POSSIBLY NOT MAKING
IT INTO MUCH OF THE IE DUE TO THIS IN UPCOMING NIGHTS.
THURSDAY THROUGH NEXT WEEKEND...
THERE WILL BE A SLIGHT COOLDOWN THROUGH FRIDAY, AS THERE WILL BE
SOME MORE INFLUENCE FROM THE TROUGHING UPSTREAM, WHICH WILL REMAIN
NEARLY LOCK-STEP IN PLACE THROUGH NEXT WEEKEND. HOWEVER, THERE WILL
BE SOME RESTRENGTHENING OF THE RIDGE, AND THUS A SLIGHT WARM UP
WITH NEARLY AVERAGE TEMPERATURES FOR THIS TIME OF YEAR GOING INTO
THE FOLLOWING WEEKEND. WITH THE TROUGH IN PLACE TO THE NORTHWEST
OF THE REGION, THIS WILL HELP TO DETER ANY MONSOONAL MOISTURE FOR
MAKING IT OVER SOCAL, AND THEREFORE ANY CHANCES FOR DEVELOPING
THUNDERSTORMS DURING THE DAYTIME HOURS SHOULD REMAIN CONFINED TO
THE EAST OF THE CALIFORNIA BORDER, WITH LIKELY ONLY SOME CUMULUS
CLOUDS DEVELOPING OVER THE MOUNTAINS.
AVIATION
270900Z....COASTS/VALLEYS...CLOUDS HAVE BEEN PRETTY SLUGGISH TO MOVE
IN THIS MORNING, BUT HAVE FILLED IN FAIRLY UNIFORMLY ACROSS COASTAL
SAN DIEGO COUNTY AND UP TO 15-20 MILES INLAND. CLOUDS ARE PATCHIER
ACROSS ORANGE COUNTY AT THIS HOUR BUT SHOULD CONTINUE TO FILL IN AND
EVENTUALLY BRING CIGS TO KSNA BY 12Z. BASES ARE GENERALLY 1700-
2000FT MSL BUT COULD LIFT 100-200FT BY 14Z. WHILE SOME CLOUDS COULD
STRETCH INTO THE WESTERN OR SOUTHERN INLAND EMPIRE AROUND BY
SUNRISE, KONT AND KSBD ONLY HAVE A 35% AND 20% CHANCE, RESPECTIVELY,
TO SEE CIGS BETWEEN 12-16Z. CLOUDS SCATTER BACK TO THE COAST BY 17-
18Z WITH VFR CONDITIONS PREVAILING THROUGH THE AFTERNOON. SIMILARLY
TO LAST NIGHT, CLOUDS RETURN TO COASTAL AREAS AROUND 03-06Z MONDAY
WITH LOWER BASES AROUND 1200-1800FT MSL. SIMILAR INLAND EXTENT UP TO
15 TO 20 MILES INLAND BUT CLOUDS SHOULD STAY OUT OF THE INLAND
EMPIRE.
MOUNTAINS/DESERTS...MOSTLY CLEAR WITH VFR CONDITIONS THROUGH
EARLY MONDAY MORNING.
MARINE
NO HAZARDOUS MARINE CONDITIONS ARE EXPECTED THROUGH THURSDAY.
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...STEWEY
AVIATION/MARINE...MUNYAN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page