298
FXHW60 PHFO 120201
AFDHFO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
401 PM HST THU DEC 11 2025
SYNOPSIS
A FRONT WILL STALL AND DISSIPATE NORTH OF THE BIG ISLAND THIS
EVENING, MAINTAINING SHOWER CHANCES FOR MAUI COUNTY THROUGH
TONIGHT. LIMITED RAINFALL IS EXPECTED FRIDAY. MODERATE
SOUTHWESTERLY WINDS AHEAD OF A STRONGER FRONT WILL INCREASE SHOWER
POTENTIAL ALONG LEEWARD AREAS SATURDAY. THE HIGHEST POTENTIAL FOR
HEAVY RAINFALL AND THUNDERSTORMS WILL DEVELOP OVER THE WESTERN
END OF THE STATE SUNDAY THROUGH TUESDAY.
DISCUSSION
AFTERNOON SATELLITE AND RADAR IMAGERY SHOWS THAT THE BAND OF LOW
LEVEL CLOUDS AND EMBEDDED LIGHT TO MODERATE SHOWERS, ASSOCIATED
WITH A WEAKENING FRONT MOVING OVER THE STATE TODAY, IS CURRENTLY
LOCATED ACROSS PRIMARILY THE ISLANDS OF MAUI COUNTY. RAINFALL
AMOUNTS TODAY HAVE BEEN MODEST AT BEST, HOWEVER, WITH THE MOST
RAIN FALLING OVER PORTIONS OF OAHU AND MOLOKAI (GENERALLY
RECEIVING UP TO A LITTLE MORE THAN HALF OF AN INCH IN THE HEAVIEST
SPOTS OVER THE PAST SIX HOURS). MEANWHILE, MODERATE NORTHERLY
WINDS HAVE FILLED IN BEHIND THE FRONT, WITH INCREASINGLY STABLE
AND DRY POST-FRONTAL CONDITIONS OBSERVED FOR KAUAI TODAY. EXPECT
A DRYING TREND FOR OAHU TONIGHT, THOUGH SHOWER CHANCES WILL
CONTINUE INTO TONIGHT FOR MAUI COUNTY AS THE FRONT STALLS AND
DISSIPATES NORTH OF THE BIG ISLAND. ADDITIONALLY, DEWPOINT
TEMPERATURES WILL DIP IN THE UPPER 50S TONIGHT AROUND KAUAI AND
EVENTUALLY OAHU AS DRIER MORE STABLE AIR FILTERS IN BEHIND THE
FRONT. WINDS WILL EASE TO LIGHT SPEEDS TONIGHT AS THE FRONT
DISSIPATES, ALLOWING LAND BREEZES TO DEVELOP. FOR THE BIG ISLAND
SUMMITS, STRONG SOUTHERLY WINDS ARE MIXING DOWN TO SUMMIT LEVEL.
THESE SHOULD GRADUALLY DECREASE THROUGHOUT THE NIGHT AS WELL,
HOWEVER. IN THE MEANTIME, A WIND ADVISORY HAS BEEN ISSUED FOR
BORDERLINE ADVISORY-LEVEL WINDS ON THE BIG ISLAND SUMMITS THROUGH
TONIGHT.
ON FRIDAY, LINGERING MOISTURE LEFTOVER FROM THE FRONT, ALONG WITH
AFTERNOON SEABREEZES, COULD TRIGGER A FEW SHOWERS ALONG LEEWARD
AND INTERIOR AREAS, ESPECIALLY AROUND MAUI COUNTY. MODERATE
SOUTHERLY WINDS WILL DEVELOP ACROSS THE STATE ON SATURDAY AS A
STRONGER FRONT APPROACHES THE ISLANDS FROM THE NORTHWEST. BY
SATURDAY NIGHT, A PRE-FRONTAL CONVERGENCE BAND IS EXPECTED TO SET
UP OVER THE WESTERN HALF OF THE STATE. THIS WILL INCREASE CHANCES
FOR SHOWERS AND THUNDERSTORMS, PARTICULARLY NEAR KAUAI AND ITS
SURROUNDING WATERS FOR SATURDAY NIGHT.
LITTLE CHANGE HAS BEEN MADE TO THE FORECAST FOR SUNDAY THROUGH
TUESDAY WITH THIS AFTERNOON'S FORECAST PACKAGE, AS IT REMAINS ON
TRACK COMPARED TO THE LATEST MODEL GUIDANCE. AN UPPER LEVEL
TROUGH WILL BECOME NEGATIVELY TILTED AND PINCH OFF INTO A LOW
SUPPORTING STRONG CYCLOGENESIS AT THE SURFACE NORTHWEST OF THE
STATE. A BAND OF HEAVY RAIN AND POTENTIAL THUNDERSTORMS
ASSOCIATED WITH THE SURFACE LOW WILL SETTLE SOMEWHERE OVER THE
WESTERN END OF THE STATE SUNDAY THROUGH MONDAY NIGHT, WITH THE
HEAVIEST RAINFALL POTENTIAL SUNDAY NIGHT INTO MONDAY. UPON THE
DEPARTURE OF SUPPORTING UPPER DYNAMICS ON TUESDAY, THE SURFACE LOW
WILL MOVE FAR NORTH OF THE STATE AND WEAKEN, LEAVING AN ORPHANED
FRONTAL MOISTURE BAND OVER THE AREA THROUGH A LEAST MID-WEEK.
EXPECT LINGERING SHOWERS OVER THE THE ISLANDS THROUGH AT LEAST
MID-WEEK. SOUTHERLY WINDS WILL PREVAIL THROUGHOUT THIS TIME.
AVIATION
LIGHT SHOWERS AND SOME LOW CLOUDS WILL CONTINUE TO SLOWLY
PROGRESS SOUTHEASTWARD ALONG A WEAK FRONT WHICH WILL STALL AND
WEAKEN OVER MAUI COUNTY. FOR THE BIG ISLAND, DRY AND MOSTLY CLEAR
CONDITIONS WILL PERSIST INTO FRIDAY.
AIRMET SIERRA FOR MOUNTAIN OBSCURATION IS NOW FOCUSED ON MOLOKAI
AND MAUI WHERE THE HIGHEST LIKELIHOOD OF LOWER CLOUDS AND SHOWERS WILL
PERSIST TONIGHT INTO FRIDAY MORNING.
FINALLY, WITH NORTH WINDS BEHIND THE FRONT AT THE SURFACE AND
WEST SOUTHWEST FLOW ALOFT, WILL BE WATCHING FOR CONTINUED LOW
LEVEL WIND SHEAR OF UP TO 20KT PHOG. THIS SHEAR IS EXPECTED TO
DIMINISH BY TONIGHT.
MARINE
A WEAK COLD FRONT IS SLOWLY PROGRESSING SOUTHEASTWARD ACROSS THE
CENTRAL WATERS AROUND MAUI THIS AFTERNOON, WHERE IT IS EXPECTED TO
STALL THIS EVENING AND DISSIPATE BY FRIDAY. GENTLE TO MODERATE
NORTHERLIES ARE FILTERING IN BEHIND THE FRONT WITH LIGHT AND
VARIABLE WINDS DOWNSTREAM. ANOTHER FRONT WILL APPROACH AND
POSSIBLY ENTER THE NORTHWESTERN COASTAL WATERS AROUND KAUAI LATE
SATURDAY INTO SUNDAY, WHERE IT WILL THEN STALL. LIGHT
SOUTHEASTERLIES WILL VEER MORE SOUTHWESTERLY AND STRENGTHEN ON
SATURDAY AS THE FRONT APPROACHES, BECOMING MORE WESTERLY BEHIND
THE FRONT. NUMEROUS SHOWERS WITH LOCALLY HEAVY RAIN AND ISOLATED
THUNDERSTORMS ARE POSSIBLE IN ASSOCIATION WITH THIS FRONTAL
BOUNDARY. THE PROXIMITY OF THIS FEATURE WILL ALSO MAINTAIN A
SOUTHERLY FLOW ACROSS MOST OF THE REGION THROUGH THE REST OF THE
FORECAST PERIOD.
A MODERATE SIZE, MEDIUM PERIOD NORTHWEST SWELL PEAKED THIS
MORNING AND WILL CONTINUE TO GRADUALLY DECLINE THIS EVENING
THROUGH FRIDAY. THEREFORE, THE HIGH SURF ADVISORY HAS BEEN
CANCELLED. ANOTHER MODERATE, LONG PERIOD NORTHWEST (310-320
DEGREE) SWELL THAT WILL BE GENERATED FROM A DEVELOPING GALE LOW
JUST NORTHWEST OF THE OFFSHORE WATERS LATE FRIDAY WILL MOVE INTO
THE REGION SUNDAY AND MONDAY. IN ADDITION, A MIX OF SMALL TO
MODERATE SIZE, MEDIUM PERIOD NORTH (350-010 DEGREE) SWELLS WILL
ARRIVE THIS WEEKEND, WITH A STRONGER PULSE EXPECTED LATE SUNDAY
INTO MONDAY, KEEPING SURF HEIGHTS ELEVATED INTO EARLY NEXT WEEK.
DUE TO THE MIX OF THESE SWELLS, SURF HEIGHTS MAY APPROACH
ADVISORY LEVELS FROM LATE SUNDAY INTO EARLY NEXT WEEK.
EAST SHORE SURF WILL REMAIN SMALL THROUGH THE FORECAST PERIOD DUE
TO THE ABSENCE OF TRADE WINDS, THOUGH LOCATIONS EXPOSED TO NORTH
SWELLS COULD SEE AN UPTICK EARLY NEXT WEEK. EXPECT MINIMAL
BACKGROUND SURF FOR SOUTH FACING SHORES, WITH THE MINOR SOUTH-
SOUTHEAST PULSE THAT ARRIVED EARLIER TODAY GRADUALLY FADING INTO
THE WEEKEND. SOUTHWESTERN EXPOSURES ON PRIMARILY KAUAI AND OAHU
MAY RECEIVE SMALL TO MODERATE CHOPPY WINDSWELL THIS WEEKEND FROM
STRENGTHENING SOUTHWEST WINDS AHEAD OF AN APPROACHING FRONT.
FIRE WEATHER
CONDITIONS WILL REMAIN BELOW CRITICAL FIRE THRESHOLDS INTO THE
WEEKEND. INCREASING SHOWER CHANCES ASSOCIATED WITH AN INCOMING
FRONT, COMBINED WITH LIGHT TO MODERATE WINDS, WILL PREVENT US FROM
REACHING CRITICAL FIRE WEATHER THRESHOLDS OVER THE NEXT SEVERAL
DAYS.
HFO WATCHES/WARNINGS/ADVISORIES
WIND ADVISORY UNTIL 6 AM HST FRIDAY FOR BIG ISLAND SUMMITS.
DISCUSSION...VAUGHAN
AVIATION...PECHACEK/TSAMOUS
MARINE...FARRIS
FIRE WEATHER...VAUGHAN
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