572  
FXUS66 KSGX 110412  
AFDSGX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SAN DIEGO CA  
812 PM PST SAT JAN 10 2026  
   
SYNOPSIS  
 
MODERATE TO LOCALLY STRONG SANTA ANA WINDS WILL CONTINUE ALONG  
THE COASTAL MOUNTAIN SLOPES, FOOTHILLS, AND INTO THE VALLEYS  
THROUGH MONDAY. PERIODS OF WEAKER SANTA ANA WINDS WILL CONTINUE  
THROUGH THE REMAINDER OF NEXT WEEK. A WARMING TREND DEVELOPS THIS  
WEEKEND, WITH TEMPERATURES PEAKING AROUND THE MIDDLE OF NEXT  
WEEK. WEDNESDAY AND THURSDAY WILL LIKELY BE THE WARMEST DAYS.  
 
 
   
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE  
 
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO  
COUNTIES...  
 
UPDATE: MILD SANTA ANA CONDITIONS CONTINUE TO IMPACT THE REGION, AND  
WILL CONTINUE TO DO SO GOING INTO THE EARLY PART OF NEXT WEEK,  
ALTHOUGH THESE WINDS ARE EXPECTED TO GRADUALLY TAPER OFF THROUGH  
THEN EACH DAY. AT THIS HOUR, THERE ARE STILL SOME WIND GUSTS OVER 50  
MPH OCCURRING WITHIN THE HIGHEST ELEVATIONS OF THE MOUNTAINS OF SAN  
DIEGO COUNTY. SILL HILL REPORTED A GUST OF 67 MPH FOR THE PREVIOUS  
OBSERVATION. EXPECT THAT THESE WINDS WILL WEAKEN FOR SOME OF THE  
INLAND AREAS ENOUGH TO ALLOW FOR SUFFICIENT RADIATIONAL COOLING, AND  
THEREFORE THERE COULD SOME AREAS OF FROST POSSIBLE WITHIN SOME OF  
THESE WIND-SHELTERED VALLEYS FOR TOMORROW MORNING. WINDS WILL  
PERIODICALLY DECOUPLE AND WEAKEN FOR SOME OF THE LOWER ELEVATIONS  
OVERNIGHT, BUT THEN INCREASE AGAIN THROUGHOUT THE LATE MORNING THRU  
AFTERNOON TOMORROW, ONCE THE WINDS MIX DOWN TO THE SURFACE. THESE  
OFFSHORE WINDS HAVE HELPED TO DRY OUT THE LOWER LEVELS, SO NO MARINE  
LAYER CLOUDS ARE ANTICIPATED THROUGH AT LEAST TUESDAY. TEMPERATURES  
WILL CONTINUE TO BE ON A GRADUAL WARMING TREND THROUGH THE MID PART  
OF NEXT WEEK, WITH MOSTLY CLEAR SKIES AND NO PRECIPITATION EXPECTED  
THROUGH THEN.  
 
PREVIOUS DISCUSSION SUBMITTED AT 130 PM:  
 
CLEAR SKIES REGION-WIDE EARLIER THIS MORNING AS MODERATE EASTERLY  
SANTA ANA WINDS CONTINUE TO FUNNEL THROUGH WEST FACING SLOPES AND  
PASSES. THE STRONGEST UPPER LEVEL NORTHERLY WINDS HAVE MOVED  
EASTWARD AND THE GUSTS HAVE REDUCED CONSIDERABLY IN THE PAST 24  
HOURS OVER THE SANTA ANA AND SAN BERNARDINO COUNTY FOOTHILLS.  
GUSTS ARE NOW 40-55 MPH AROUND THE CAJON PASS AND MOSTLY BELOW 40  
MPH THOUGH THE INLAND EMPIRE AND ORANGE COUNTY INLAND AREAS.  
 
THE SURFACE PRESSURE GRADIENT BETWEEN SOUTHERN CALIFORNIA AND AREAS  
A FEW HUNDRED MILES EAST AND NORTHEAST OF US REMAINS STRONG,  
ALLOWING FOR ELEVATED WINDS TO CONTINUE FOR THE AREAS MENTIONED  
ABOVE AS WELL AS STRONG EAST WINDS OVER THE SAN DIEGO COUNTY  
MOUNTAINS. GUSTS 50-65 MPH AND LOCALLY HIGHER ARE EXPECTED FOR THE  
SAN DIEGO COUNTY MOUNTAIN WESTERN SLOPES NEAR PEAKS AND PASSES  
THROUGH EARLY MONDAY. WINDS REDUCE SLIGHTLY THEREAFTER BUT REMAIN  
STRONG WITH PERIODS OF GUSTS TO 50 MPH REMAIN POSSIBLE THROUGH AT  
LEAST WEDNESDAY, AS EASTERLY 700 MB WINDS REMAIN ROBUST. THERE IS  
SOME UNCERTAINTY REGARDING THE SANTA ANA WINDS AFTER WEDNESDAY,  
ALTHOUGH MOST MODEL GUIDANCE SUGGESTS A CONTINUATION OF THE OFFSHORE  
FLOW. THE CW3E WRF MAINTAINS WEAK TO MODERATE NORTHEAST AND EAST  
PRESSURE GRADIENTS BETWEEN SOCAL AND THE INTERIOR THROUGH NEXT  
FRIDAY. MEDIUM RANGE MODELS CONTINUE TO HIGHLIGHT MODEST MID-LEVEL  
EASTERLY FLOW OVER OUR REGION UNTIL AT LEAST NEXT WEEKEND.  
 
DUE TO THE ABUNDANCE OF DRY AIR AT THE SURFACE, NIGHTTIME  
TEMPERATURES WILL DROP INTO THE 30S IN WIND-SHELTERED VALLEYS  
TONIGHT AND POTENTIALLY SUNDAY NIGHT. AT THE SAME TIME, HIGH  
TEMPERATURES WILL BE INCREASING A FEW DEGREES EACH DAY THROUGH  
WEDNESDAY. LOWLAND TEMPERATURES TOP OUT AROUND 70 DEGREES TODAY AND  
ARE EVENTUALLY FORECAST TO TOP OUT AROUND 80 DEGREES WEDNESDAY  
AFTERNOON.  
 
WPC 500MB HEIGHT CLUSTERS ARE IN GOOD AGREEMENT THAT THE STRONG  
UPPER LONGWAVE RIDGE OVER THE PACIFIC NORTHWEST WILL CONTINUE TO  
AMPLIFY NORTHWARD. WHILE THE RIDGE AXIS WILL CONTINUE TO BE LINED UP  
ALONG THE WEST COAST, SOCAL MAY BE FAR ENOUGH SOUTH ENOUGH TO SEE  
HEIGHTS COME DOWN SLIGHTLY WITH AN OUTSIDE CHANCE FOR AN UPPER  
CUTOFF LOW TO DEVELOP OVER NORTHWEST MEXICO AND BRING DOWN  
TEMPERATURES NEAR AVERAGE AND ENHANCE CLOUD COVER. NEVERTHELESS,  
THERE IS MODERATE CONFIDENCE FOR PEAK TEMPERATURES NEXT WEEK TO  
OCCUR WEDNESDAY AND THURSDAY, THEN COOL OFF SLIGHTLY INTO THE  
WEEKEND.  
 
AS LONG AS THE OFFSHORE FLOW PERSISTS, RELATIVE HUMIDITY WILL  
REMAIN LOW. DAYTIME RH DROPS INTO THE 10-20% RANGE THROUGH AT  
LEAST TUESDAY , WITH OVERNIGHT RECOVERIES CAPPED AT ONLY 35-40%  
FOR MOST OF THE REGION. FIRE DANGER WILL BE ELEVATED AS A RESULT  
ALTHOUGH LIMITED AS THE FUEL MOISTURE LEVELS ARE HIGH FROM RECENT  
RAINS.  
 
 
   
AVIATION  
 
110330Z...COAST/VALLEYS/MOUNTAINS...CLEAR SKIES PREVAILING.  
NORTHEAST AND EAST WINDS GUSTING GENERALLY 30-45 KTS ALONG COASTAL  
SLOPES WITH 25-40 KTS DOWNWIND OF THE CAJON/BANNING PASSES INTO THE  
INLAND EMPIRE AND PARTS OF INLAND ORANGE COUNTY/EASTERN SAN DIEGO  
VALLEYS. LIGHTER SURFACE WINDS OVERNIGHT WITH PERIODS OF LLWS WITH  
MOD UP/DOWNDRAFTS DOWNWIND OF COASTAL SLOPES THROUGH 18Z SUN.  
OFFSHORE WIND PATTERN CONTINUES THROUGH THE REMAINDER OF THE  
WEEKEND, WITH SLIGHTLY WEAKER WINDS BY MONDAY MORNING AND THE  
STRONGEST GUSTS MORE CONFINED TO THE MOUNTAIN SLOPES.  
 
DESERTS...VFR CONDITIONS THROUGH SUNDAY EVENING. ELEVATED NORTHEAST  
WINDS STAYING MOSTLY CONFINED TO DESERT FOOTHILLS WITH GUSTS 15-25  
KTS.  
 
 
   
MARINE  
 
LOCALIZED EASTERLY WIND GUSTS NEAR 20 TO 25 KNOTS SPORADICALLY  
THROUGH THIS WEEKEND. OTHERWISE, NO HAZARDOUS MARINE CONDITIONS  
EXPECTED THROUGH WEDNESDAY.  
 
 
   
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 ORANGE COUNTY INLAND  
AREAS-RIVERSIDE COUNTY MOUNTAINS-SAN BERNARDINO AND  
RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SAN DIEGO COUNTY  
VALLEYS-SANTA ANA MOUNTAINS AND FOOTHILLS.  
 
HIGH WIND WARNING UNTIL 1 PM PST SUNDAY FOR SAN BERNARDINO  
COUNTY MOUNTAINS-SAN DIEGO COUNTY MOUNTAINS-SAN GORGONIO  
PASS NEAR BANNING.  
 
PZ...NONE.  
 
 
 
 
 
UPDATE...STEWEY  
PUBLIC...WESTERINK  
AVIATION/MARINE...ZUBER  
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