674
FXUS66 KSGX 091109
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
309 AM PST FRI JAN 9 2026
SYNOPSIS
MODERATE TO LOCALLY STRONG SANTA ANA WINDS WILL CONTINUE ALONG
THE COASTAL MOUNTAIN SLOPES, FOOTHILLS, AND INTO THE VALLEYS
THROUGH SUNDAY. PERIODS OF WEAKER SANTA ANA WINDS WILL CONTINUE
BEYOND THAT. PATCHY FROST IS EXPECTED THIS MORNING IN WIND
SHELTERED VALLEY LOCATIONS. A WARMING TREND DEVELOPS THIS WEEKEND,
WITH TEMPERATURES PEAKING AROUND THE MIDDLE OF NEXT WEEK.
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
NOT A CLOUD IN THE SKY THIS MORNING, LEAVING US WITH ONLY WINDS TO
FOCUS ON. THE OFFSHORE FLOW AND SANTA ANA WINDS HAVE BEGUN IN
EARNEST, WITH SOME FOOTHILL SPOTS GUSTING OVER 50 MPH, AND EVEN
SOME VALLEY LOCATIONS GUSTING OVER 30 MPH. THESE WINDS WILL MOST
LIKELY PEAK TODAY IN THE LATE MORNING THROUGH EARLY AFTERNOON. TOP
GUSTS IN THE TOP SPOTS WILL ACHIEVE 60+ MPH WITH REALLY ISOLATED
GUSTS CLOSE TO 80 MPH. WINDS CONTINUE QUITE RELENTLESS IN THESE
AREAS THROUGH THE WEEKEND, ONLY SLIGHTLY WEAKER AND SLIGHTLY LESS
WIDESPREAD THAN TODAY'S WINDS. YESTERDAY'S COLD SYSTEM THAT DOVE
INTO ARIZONA HAS SET UP EFFICIENT OFFSHORE FLOW BOTH ALOFT AND AT
THE SURFACE. WHILE THE UPPER SUPPORT WEAKENS SLIGHTLY, THE SURFACE
GRADIENT TIGHTENS SLIGHTLY, SO NEARLY A WASH AS FAR AS THE WIND
TRENDS GO. FIRE POTENTIAL RISES AS HUMIDITY DIPS DURING THIS WINDY
EVENT, BUT THE FUEL MOISTURES REMAIN QUITE HIGH (GREEN AND GROWING
VEGETATION FROM RECENT RAINS) TO THANKFULLY MITIGATE THE FIRE
POTENTIAL. THERE ARE SOME FROSTY CONDITIONS IN PARTS OF THE INLAND
WIND-SHELTERED VALLEYS THIS MORNING. AN UPPER RIDGE OF HIGH
PRESSURE BUILDS OVER CALIFORNIA THIS WEEKEND AND CONTINUES TO
EXPAND AND STRENGTHEN NEXT WEEK. BUT WITH LOW PRESSURE OVER
NORTHWEST MEXICO, THE FLOW ALOFT CONTINUES TO BE OFFSHORE
(NORTHEAST). SURFACE GRADIENTS WEAKEN SO WINDS SHOULD ALSO WEAKEN
A LITTLE, BUT AREAS OF GUSTY WINDS WILL PERSIST. IT'S GOING TO BE
A REALLY LONG SANTA ANA EPISODE. A STEADY WARMING TREND WILL
BOOST TEMPERATURES A COUPLE DEGREES EACH DAY INTO WEDNESDAY. LOOK
FOR LOTS OF 70S EMERGING AT LOWER ELEVATIONS THIS WEEKEND. BY
WEDNESDAY THERE SHOULD BE SOME AREAS REACHING INTO THE 80S. THE
DRY AIR MASS WILL ALLOW TEMPS TO DROP EFFICIENTLY EACH NIGHT,
ESPECIALLY WHEN/WHERE WINDS CALM DOWN, BUT NIGHTTIME TEMPS WILL
REMAIN REALLY MILD IN THE 60S IN THOSE AREAS WHERE MIXING WINDS
PERSIST. NO MEANINGFUL CHANGE IN THE PATTERN IS SHOWN BY ENSEMBLES
TOWARD NEXT WEEKEND. SOME SOLUTIONS SHOW AN ARCTIC BLAST COMING
DOWN THE INTERIOR WEST. OTHERS KEEP THE RIDGE FIRMLY IN PLACE
ALONG THE WEST COAST. CONFIDENCE IS HIGH OUR WEATHER WILL REMAIN
DRY AND WARM INTO NEXT WEEKEND.
AVIATION
091100Z...COAST/VALLEYS/MOUNTAINS...NORTHEAST WINDS CURRENTLY
GUSTING 40-55 KTS ALONG COASTAL SLOPES MOSTLY NORTH OF SAN DIEGO
COUNTY. GUSTS 25-40 KTS THROUGH THE INLAND EMPIRE FROM KONT TO KRIV,
AND INTO INLAND ORANGE COUNTY (INCLUDING KSNA). CORRIDORS OF STRONG
WINDS WEAKEN SLIGHTLY FRIDAY AFTERNOON BEFORE TURNING MORE EASTERLY
AROUND 21Z FRI-03Z SAT. WINDS ALSO EXPAND IN COVERAGE TO INCLUDE
MORE OF SAN DIEGO COUNTY AND MORE OF THE INLAND VALLEYS. PERIODS OF
LLWS AND MODERATE UP AND DOWNDRAFTS DOWNWIND OF COASTAL SLOPES
(I.E. KONT, KSNA, KSBD).
DESERTS...VFR CONDITIONS THROUGH THE PERIOD. STRONG NORTHEAST WIND
GUSTS SHOULD STAY MOSTLY CONFINED TO MOUNTAIN SLOPES, ESPECIALLY
AFTER 18Z FRI.
MARINE
NORTHEAST TO EAST WINDS WILL OCCASIONALLY GUST TO 20 KNOTS THIS
WEEKEND. OTHERWISE, NO HAZARDOUS MARINE CONDITIONS EXPECTED THROUGH
TUESDAY NIGHT.
SKYWARN
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
SGX WATCHES/WARNINGS/ADVISORIES
CA...WIND ADVISORY UNTIL 1 PM PST SUNDAY FOR RIVERSIDE COUNTY
MOUNTAINS-SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE
INLAND EMPIRE-SAN DIEGO COUNTY MOUNTAINS-SAN GORGONIO PASS
NEAR BANNING-SANTA ANA MOUNTAINS AND FOOTHILLS.
WIND ADVISORY FROM 8 AM THIS MORNING TO 1 PM PST SUNDAY FOR SAN
DIEGO COUNTY VALLEYS.
HIGH WIND WARNING UNTIL 1 PM PST SUNDAY FOR SAN BERNARDINO
COUNTY MOUNTAINS.
WIND ADVISORY UNTIL 1 PM PST SATURDAY FOR ORANGE COUNTY INLAND
AREAS.
PZ...NONE.
PUBLIC...MM
AVIATION/MARINE...KW
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