129
FXHW60 PHFO 191250
AFDHFO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
250 AM HST TUE AUG 19 2025
SYNOPSIS
MODERATE TO LOCALLY BREEZY TRADE WINDS WILL CONTINUE THROUGH THE
WEEK AS HIGH PRESSURE BUILDS OVER THE REGION. ANOTHER PLUME OF
MOISTURE LOOKS TO BRING A SLIGHT INCREASE IN WINDWARD AND MAUKA
SHOWERS ON WEDNESDAY. OTHERWISE, EXPECT A GRADUAL DRYING TREND
THROUGH THE WEEK, WITH TYPICAL SUMMERTIME TRADE WIND WEATHER.
DISCUSSION
RADAR AND SATELLITE IMAGERY SHOW SOME LOW LEVELS CLOUDS AND
SCATTERED SHOWERS MOVING ACROSS THE STATE THIS MORNING. WINDWARD
AND MAUKA SHOWERS EXPECTED ACROSS THE STATE THROUGH THE OVERNIGHT
AND EARLY MORNING HOURS.
HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE ISLANDS WITH
MODERATE TO LOCALLY BREEZY TRADE WINDS CONTINUING THROUGH THE
WEEK. GUIDANCE CONTINUES TO SHOW ANOTHER PLUME OF MOISTURE MOVING
ACROSS THE ISLANDS ON WEDNESDAY WHICH MAY BRING A SLIGHT INCREASE
IN CLOUDS AND SHOWERS OVER WINDWARD AND MAUKA AREAS. OTHERWISE,
THE GRADUAL DRYING TREND WILL CONTINUE THROUGH THE WEEK WITH THE
TYPICAL SUMMERTIME TRADE WIND WEATHER (DRY AND STABLE CONDITIONS).
WITH DRY AND BREEZY CONDITIONS EXPECTED LATER THIS WEEK WE WILL
SEE ELEVATED FIRE WEATHER CONCERNS, ESPECIALLY ACROSS LEEWARD
AREAS.
AVIATION
MODERATE TO LOCALLY BREEZY TRADES EXPECTED THROUGH THE FORECAST
PERIOD. LOW CIGS AND SHRA POSSIBLE OVER WINDWARD AND MAUKA AREAS.
MVFR CONDS POSSIBLE IN SHRA, OTHERWISE VFR PREVAILS.
NO AIRMETS ARE IN EFFECT AT THIS TIME.
MARINE
A RIDGE OF HIGH PRESSURE FAR NORTH OF THE STATE WILL MAINTAIN
FRESH TO LOCALLY STRONG TRADE WINDS THROUGHOUT THE FORECAST
PERIOD. A SMALL CRAFT ADVISORY (SCA) IS IN EFFECT FOR THE WINDIER
WATERS AND CHANNELS AROUND MAUI COUNTY AND THE BIG ISLAND THROUGH
TONIGHT AND WILL LIKELY PERSIST THROUGHOUT THE WEEK.
A SERIES OF SMALL, MEDIUM PERIOD SOUTH (170-190 DEGREE) SWELLS
ARE EXPECTED THROUGHOUT THE WEEK WITH SURF HOLDING NEAR THE SUMMER
AVERAGE. SURF HEIGHTS SHOULD DECREASE SUNDAY INTO EARLY NEXT WEEK
AS THESE SWELLS FADE. CHOPPY CONDITIONS WILL CONTINUE FOR EAST-
FACING SHORES THROUGH THE FORECAST PERIOD DUE TO THE PERSISTENT
FRESH TRADES. SURF ALONG NORTH FACING SHORES WILL REMAIN FLAT TO
TINY THROUGH THE FORECAST PERIOD.
PEAK HIGH TIDES ASSOCIATED WITH THE LUNAR CYCLE WILL LEAD TO MINOR
COASTAL FLOODING ALONG SHORELINES AND LOW LYING COASTAL AREAS THIS
AFTERNOON AND LIKELY PEAKING WEDNESDAY AND THURSDAY AFTERNOONS.
A COASTAL FLOOD STATEMENT HAS BEEN ISSUED FOR MINOR COASTAL
FLOODING THIS WEEK.
FIRE WEATHER
MODERATE TO LOCALLY BREEZY TRADE WINDS EXPECTED THIS WEEK AS HIGH
PRESSURE BUILDS OVER THE STATE. BORDERLINE FIRE WEATHER
CONDITIONS POSSIBLE ON TUESDAY AS DRIER AIR STARTS TO FILTER INTO
THE REGION. ANOTHER PLUME OF MOISTURE MAY BRING A SLIGHT INCREASE
IN HUMIDITY AND SHOWERS ON WEDNESDAY. ELEVATED FIRE WEATHER
CONDITIONS POSSIBLE BEYOND WEDNESDAY AS STABLE AND DRIER
CONDITIONS DEVELOP AND THE TRADE WIND INVERSION LOWERS TO AROUND
5000-6000 FEET. BREEZY TRADE WINDS AND AFTERNOON RELATIVE HUMIDITY
IN THE UPPER 40S TO LOWER 50S MAY REQUIRE FIRE WEATHER HEADLINES
TO BE ISSUED IN THE COMING DAYS.
HFO WATCHES/WARNINGS/ADVISORIES
SMALL CRAFT ADVISORY UNTIL 6 AM HST WEDNESDAY FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.
DISCUSSION...WALSH
AVIATION...WALSH
MARINE...SHIGESATO
FIRE WEATHER...WALSH
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