689
FXHW60 PHFO 040121
AFDHFO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
321 PM HST TUE MAR 3 2026
SYNOPSIS
SURFACE HIGH PRESSURE WILL CONTINUE TO BUILD NORTHEAST OF THE
STATE THROUGH WEDNESDAY AND BRING LOCALLY BREEZY EASTERLY TRADE
WINDS. BRIEF PASSING SHOWERS WILL FAVOR WINDWARD AND MOUNTAIN
AREAS, MAINLY DURING THE OVERNIGHT AND EARLY MORNING HOURS.
LATE WEDNESDAY THROUGH THIS WEEKEND, TRADE WINDS WILL EASE
SLIGHTLY AND VEER TO A MORE EAST-SOUTHEAST DIRECTION, SHIFTING
SHOWER ACTIVITY OVER EAST AND SOUTHEAST FACING SLOPES OF MOST
ISLANDS. HOWEVER, OVERALL RAINFALL AMOUNTS ARE EXPECTED TO REMAIN
LIMITED. AN APPROACHING FRONT MAY BRING UNSETTLED WET WEATHER BY
EARLY TO MID NEXT WEEK.
DISCUSSION
VISIBLE SATELLITE IMAGERY SHOWS A MUCH DRIER SCENE THIS AFTERNOON
COMPARED TO THIS MORNING, WITH ABUNDANT SUNSHINE ACROSS THE STATE
AND ONLY LIMITED LOW CLOUDS AND ISOLATED LIGHT SHOWERS MOVING
INTO WINDWARD AND MAUKA AREAS. ALTHOUGH THE TRADE FLOW REMAINS
PRIMARILY OUT OF THE EAST, THE LOW-LEVEL STEERING FLOW IS
BEGINNING TO TAKE ON A SLIGHT SOUTHERLY COMPONENT, AS EVIDENCED BY
CLOUDS AND SHOWERS MOVING MORE PARALLEL TO THE ISLAND CHAIN IN AN
EAST-SOUTHEAST DIRECTION.
HIGH PRESSURE TO THE NORTHEAST OF THE STATE WILL CONTINUE TO
BUILD THROUGH MIDWEEK, BRINGING INCREASED STABILITY AND
STRENGTHENING TRADES THROUGH WEDNESDAY. LIMITED CLOUDS AND LIGHT
SHOWERS WILL GENERALLY FAVOR WINDWARD AND MAUKA AREAS THROUGH THIS
PERIOD, ESPECIALLY DURING THE OVERNIGHT TO EARLY MORNING HOURS,
ALONG WITH THE KONA SLOPES OF THE BIG ISLAND DURING THE AFTERNOON
HOURS.
BY THURSDAY, WINDS WILL VEER OUT OF A MORE EAST-SOUTHEAST
DIRECTION AS A COLD FRONT APPROACHES FROM THE NORTHWEST. IN THIS
PATTERN, SHOWERS WILL FAVOR SOUTHEAST AND EAST FACING SLOPES OF
THE BIG ISLAND AND MAUI, ALONG WITH INTERIOR PORTIONS OF THE OTHER
ISLANDS DUE TO THE DEVELOPMENT OF SEA BREEZES IN THE LIGHTER,
SOMEWHAT BLOCKED FLOW. MODEL GUIDANCE REMAINS IN GOOD AGREEMENT
THROUGH THIS PERIOD, SHOWING THIS FRONT STALLING JUST TO THE WEST
OF THE STATE AS ITS PARENT LOW SHOOTS OFF TO THE FAR NORTHWEST.
THE EVOLUTION OF WEATHER FEATURES IN THE PACIFIC BECOMES LESS
CLEAR OVER THE WEEKEND AS MODEL SPREAD INCREASES. THE GFS AND THE
ECMWF BOTH SHOW A DEEP MID- TO UPPER-LEVEL TROUGH DEVELOPING
NORTHWEST OF THE STATE, SPAWNING A SURFACE LOW TO THE WEST-
NORTHWEST. STRENGTHENING SOUTHERLY FLOW BETWEEN THAT LOW AND HIGH
PRESSURE TO OUR NORTHEAST COULD DRAW DEEP TROPICAL MOISTURE (WITH
PRECIPITABLE WATER VALUES NEAR 2 INCHES) TOWARD OR OVER THE
WESTERN END OF THE STATE EARLY TO MID NEXT WEEK. THE EXACT
PLACEMENT OF THIS MOISTURE BAND AND THE STRENGTH OF THE SOUTHERLY
WINDS REMAIN UNCERTAIN AND WILL BE MONITORED CLOSELY IN THE COMING
DAYS.
AVIATION
STABLE TRADE WINDS WILL STRENGTHEN TO FRESH TO STRONG LEVELS AND
BECOME MORE EASTERLY TONIGHT INTO WEDNESDAY, DELIVERING CLOUDS
AND SHOWERS MAINLY WINDWARD AND MAUKA. POCKETS OF MVFR ARE LIKELY,
BUT VFR IS FORECAST TO PREVAIL DURING THIS TIME. AIRMET TANGO FOR
LEE TURB IS IN EFFECT AND WILL SHOULD REMAIN IN PLACE THROUGH
WEDNESDAY.
MARINE
FRESH TO STRONG TRADE WINDS WILL BUILD AND BECOME INCREASINGLY
EASTERLY ON WEDNESDAY AS SURFACE HIGH PRESSURE STRENGTHENS FAR
NORTHEAST OF THE ISLANDS. WEDNESDAY NIGHT INTO THURSDAY, WINDS
WILL VEER OUT OF THE EAST-SOUTHEAST AROUND OAHU AND KAUAI AS THE
HIGH DRIFTS EASTWARD AND BROAD LOW PRESSURE DEVELOPS NORTHWEST OF
THE STATE. A SMALL CRAFT ADVISORY (SCA) IS IN EFFECT FOR THE
TYPICALLY WINDY WATERS AROUND THE BIG ISLAND AND MAUI COUNTY
TODAY, THEN EXPANDS TO WINDWARD WATERS OF BIG ISLAND AND MAUI
COUNTY TONIGHT AND WEDNESDAY AS VEERING WINDS LEAD TO
ACCELERATIONS NORTH OF THOSE ISLANDS. MINOR ADJUSTMENTS WILL NEED
TO BE MADE, BUT THE SCA WILL LIKELY CONTINUE FOR SOME AREAS
THROUGH THE WEEKEND. AS LOW PRESSURE SLOWLY ADVANCES TOWARD THE
ISLANDS EARLY NEXT WEEK, LOCAL WINDS COULD VEER INCREASINGLY
SOUTHERLY.
THE CURRENT MODERATE NORTHWEST SWELL WILL CONTINUE A GRADUAL
DECLINE THROUGH THURSDAY. A SMALL WEST-NORTHWEST SWELL WILL
ARRIVE ON FRIDAY AND HOLD THROUGH THE WEEKEND, FOLLOWED BY A
SMALL NORTH-NORTHWEST SWELL EARLY NEXT WEEK. CHOPPY EAST SHORE
SURF WILL BUILD TO NEAR SEASONAL AVERAGE BY WEDNESDAY AS TRADE
WINDS STRENGTHEN OVER AND EAST OF THE ISLANDS. LITTLE CHANGE IS
EXPECTED ALONG EAST FACING SHORES THROUGH THE WEEKEND, FOLLOWED
BY A POSSIBLE DECLINE EARLY NEXT WEEK IF WINDS VEER SOUTHERLY.
SURF ALONG SOUTH FACING SHORES WILL REMAIN SMALL TO TINY THROUGH
THE WEEKEND, AND SOME ISLANDS MAY AN INCREASE IN CHOPPY SURF IF
SOUTHERLY WINDS DEVELOP EARLY NEXT WEEK.
A COASTAL FLOOD STATEMENT REMAINS IN EFFECT THROUGH EARLY
WEDNESDAY MORNING DUE TO THE COMBINATION OF PEAK MONTHLY HIGH
TIDES AND WATER LEVELS THAT ARE RUNNING HIGHER THAN PREDICTED.
THIS MAY LEAD TO MINOR FLOODING ALONG THE SHORELINE AND IN LOW-
LYING COASTAL AREAS DURING THE HIGH TIDE BETWEEN MIDNIGHT AND
DAYBREAK.
HFO WATCHES/WARNINGS/ADVISORIES
SMALL CRAFT ADVISORY UNTIL 6 AM HST THURSDAY FOR MAUI COUNTY
WINDWARD WATERS-BIG ISLAND WINDWARD WATERS.
SMALL CRAFT ADVISORY UNTIL 6 AM HST THURSDAY FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.
DISCUSSION...FARRIS
AVIATION...JVC
MARINE...WROE
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