694
FXUS66 KSGX 300810
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
1210 AM PST TUE DEC 30 2025
SYNOPSIS
CLOUDIER CONDITIONS WITH WARM WEATHER IS EXPECTED TODAY. SANTA
ANA WINDS REMAIN GUSTY THIS MORNING, THEN WEAKEN BY THIS EVENING
ACROSS THE MOUNTAINS AND WESTERN VALLEYS. A LOW PRESSURE SYSTEM
WILL BRING PERIODS OF SHOWERS FOR NEW YEAR'S EVE AND NEW YEAR'S
DAY WITH THE POTENTIAL FOR MORE CLOUDIER AND WET WEATHER BY THE
END OF THE WEEK INTO EARLY NEXT WEEK.
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
SANTA ANA WINDS CONTINUE THIS MORNING ACROSS THE MOUNTAINS AND
PARTS OF THE WESTERN VALLEYS AS A SURFACE HIGH STRADDLES THE
UTAH-NEVADA BORDER. WINDS WILL PEAK IN INTENSITY AFTER SUNRISE
WITH GUSTS NEAR 25-45 MPH, LOCALLY HIGHER ACROSS MOUNTAIN PEAKS
AND PASSES. THE SANTA ANA WIND PATTERN WILL MAKE FOR ANOTHER WARM
DAY WEST OF THE MOUNTAINS WITH PLENTIFUL HIGHS IN THE 70S; EVEN
PARTS OF EAST COUNTY SAN DIEGO MAY REACH NEAR 80 DEGREES. THE
PRESSURE GRADIENT WILL BEGIN TO RELAX BY TUESDAY AFTERNOON AND
EVENING, LEADING TO WEAKER WINDS.
A WELL DEFINED AREA OF LOW PRESSURE TO OUR SOUTHWEST THAT GAVE US
A NICE SUNSET LAST EVENING FOR SOME FOLKS WILL BEGIN TO MOVE
NORTHWARD ON WEDNESDAY. MODELS CONTINUE TO SLIGHTLY DELAY ONSET OF
PRECIPITATION OCCURRING, WITH A BETTER CONSENSUS FRAMED AROUND
WEDNESDAY MORNING. A VERY DRY ATMOSPHERIC PROFILE TODAY WILL TAKE
IT'S TIME MOISTENING UP ON WEDNESDAY, SO SHOWERS IN THE MORNING
LOOK FAIRLY LIGHT WITH SOUTH-FACING SLOPES OF THE SAN BERNARDINO
MTS RECEIVING THE MOST APPRECIABLE AMOUNTS THROUGH THE AFTERNOON
HOURS. RAIN SHOWERS WILL BECOME MORE WIDESPREAD AND A BIT HEAVIER
BY WEDNESDAY EVENING THROUGH THURSDAY MORNING. THE WEATHER SYSTEM
WILL ALSO BRING INCREASING SOUTHERLY WINDS, WHERE CONFIDENCE IS
INCREASING IN SEEING WIND GUSTS AT THE COAST NEAR 20 MPH AT TIMES.
THIS MAY IMPACT THE NEW YEAR'S FESTIVITIES WHEREVER YOU ARE, SO
PLAN ACCORDINGLY!
COASTAL MOUNTAIN SLOPES AND ORANGE COUNTY WILL RECEIVE THE
MAJORITY OF THE RAIN; HIGHEST TOTALS ACROSS SAN BERNARDINO COUNTY
MTS. THROUGH THURSDAY NIGHT NEARING 2-4 INCHES. CHANCES FOR ONE
INCH OR MORE OF RAIN VARY IN ORANGE COUNTY NEAR 50-70%, CLOSER TO
25-50% IN WESTERN SAN DIEGO COUNTY. THE DESERTS LOOK TO RECEIVE
RAIN, BUT IT WILL BE LIGHT (MAINLY UNDER ONE HALF INCH). A BREAK
IN THE RAIN LOOKS INCREASINGLY LIKELY BY LATE THURSDAY INTO FRIDAY
AS THE SYSTEM DEPARTS AND IS REPLACED BY A WEAK RIDGE OVER THE
AREA. SOME AREAS OF CLEAR SKIES MAY OCCUR, ESPECIALLY ACROSS THE
DESERT REGIONS. COOLER WITH HIGHS NEAR AVERAGE AND MORE HUMID
WEATHER WILL LAST THROUGH THIS PERIOD AS WELL.
A LOW PRESSURE SYSTEM IN THE GULF OF ALASKA WILL BE MOVING
SOUTHWARD TOWARD THE WEST COAST THIS WEEK. MODEL TRENDS CONTINUE A
SUBTLE SHIFT IN THE WEATHER SYSTEM'S PLACEMENT FURTHER NORTH,
LEADING TO DECREASING CHANCES FOR RAINFALL ACROSS OUR REGION BY
FRIDAY NIGHT INTO SATURDAY. CLOUDIER AND COOLER CONDITIONS ARE
EXPECTED, BUT THE BEST CHANCE FOR RAIN WILL BE FOR AREAS CLOSER TO
THE LA BASIN. MODEL GUIDANCE BEGINS TO GREATLY DIVERGE BY EARLY
NEXT WEEK. ANOTHER LOW PRESSURE SYSTEM OFF THE COAST MAY CONTINUE
A CHANCE FOR MORE RAINFALL OR A RIDGE OVER MEXICO MAY BEGIN TO
BUILD IN, RESULTING IN DRIER AND WARMER WEATHER. NBM CONTINUES
RAIN CHANCES INTO EARLY NEXT WEEK, THOUGH CHANCES REMAIN LOW NEAR
30% OR LOWER FOR MEASURABLE RAINFALL.
AVIATION
300600Z...VFR CONDITIONS THROUGH THE TAF PERIOD WITH INCREASING
COVERAGE OF BKN-OVC HIGH CLOUDS AOA 20,000FT. GUSTY OFFSHORE WINDS
HAVE LARGELY RELAXED ACROSS THE REGION, WITH LOCALIZED GUSTS NEAR 20-
30 KTS POSSIBLE IN THE MOUNTAIN PASSES AND COASTAL SLOPES OVERNIGHT.
INSTANCES OF LLWS REMAINS POSSIBLE AS SURFACE GUSTS HAVE WANED,
THOUGH WINDS ALOFT CONTINUE TO DECREASE THROUGH 09Z TUESDAY AS WELL.
20-30 KT WINDS PREVAIL FOR THE MOUNTAIN PASSES AND COASTAL MOUNTAIN
SLOPES THROUGH TUESDAY AFTERNOON, BUT WILL BE MORE CONFINED TO THESE
TYPICAL LOCATIONS COMPARED TO TODAY. ELEVATED OFFSHORE WINDS CEASE
BETWEEN 00-06Z WEDNESDAY.
MARINE
NO HAZARDOUS MARINE WEATHER CONDITIONS EXPECTED THROUGH SATURDAY.
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 TUESDAY FOR SAN BERNARDINO COUNTY
MOUNTAINS-SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE
INLAND EMPIRE-SAN DIEGO COUNTY MOUNTAINS-SAN DIEGO COUNTY
VALLEYS-SAN GORGONIO PASS NEAR BANNING-SANTA ANA MOUNTAINS
AND FOOTHILLS.
PZ...NONE.
PUBLIC...APR
AVIATION/MARINE...MUNYAN
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