861
FXHW60 PHFO 200157
AFDHFO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
357 PM HST TUE AUG 19 2025
SYNOPSIS
MODERATE TO LOCALLY BREEZY TRADE WINDS WILL CONTINUE THROUGH THE
REST OF THIS WEEK AS HIGH PRESSURE BUILDS OVER THE REGION. A
SUBTLE INCREASE IN WINDWARD AND MAUKA SHOWERS IS POSSIBLE ON
WEDNESDAY, BUT IN GENERAL, EXPECT MOSTLY DRY AND STABLE CONDITIONS
INTO THE WEEKEND.
DISCUSSION
LATEST RADAR AND SATELLITE IMAGERY THIS AFTERNOON SHOWS MOSTLY
DRY CONDITIONS PREVAILING ACROSS THE ISLANDS WITH RELATIVELY FEW
CLOUDS AND ALMOST NO SHOWERS AS HIGH PRESSURE BUILDS OVER THE
REGION. MODERATE TO LOCALLY BREEZY TRADE WINDS ARE OBSERVED AT
MOST LOCATIONS, WITH THE HIGHEST GUSTS GENERALLY IN THE 20 TO 30
MPH RANGE. AFTERNOON SOUNDINGS FROM HILO AND LIHUE SHOW THE TRADE
WIND INVERSION BETWEEN 5000 AND 6000 FEET.
GUIDANCE INDICATES THAT RIDGING WILL REMAIN IN PLACE FOR THE NEXT
SEVERAL DAYS, WHICH WILL CONTINUE THE BREEZY TRADES THROUGH THE
END OF THE WEEK. AS PREVIOUS DISCUSSIONS HAVE MENTIONED, GUIDANCE
CONTINUES TO SHOW THAT A SUBTLE PLUME OF MOISTURE WILL MOVE ACROSS
THE ISLANDS DURING THE DAY ON WEDNESDAY, WHICH MAY BRING A SLIGHT
INCREASE IN CLOUDS AND SHOWERS OVER WINDWARD AND MAUKA AREAS
(THOUGH THIS WOULD BE SUBTLE). OTHER THAN THIS, HOWEVER, AN
OVERALL DRY TREND WILL CONTINUE THROUGH THE WEEK WITH THE TYPICAL
SUMMERTIME TRADE WIND WEATHER AND DRY, STABLE CONDITIONS. WITH THE
DRY AND BREEZY CONDITIONS THROUGHOUT THE REST OF THIS WEEK AND
INTO THE WEEKEND, WE COULD SEE ELEVATED FIRE WEATHER CONCERNS,
ESPECIALLY ACROSS LEEWARD AREAS.
NEXT WEEK, A PLUME OF MOISTURE EMBEDDED WITHIN THE TRADES COULD
MOVE INTO THE ISLANDS BY MONDAY OR TUESDAY, INCREASING WINDWARD
AND MAUKA CLOUDS AND SHOWERS ONCE AGAIN.
AVIATION
MODERATE TO LOCALLY BREEZY TRADES WILL PERSIST THROUGH THE
FORECAST PERIOD. LOW CIGS AND SHRA ARE POSSIBLE OVER WINDWARD AND
MAUKA AREAS. MVFR CONDS POSSIBLE IN SHRA, OTHERWISE VFR PREVAILS.
NO AIRMETS ARE IN EFFECT AT THIS TIME. AIRMET SIERRA MAY BE
NEEDED OVERNIGHT DUE TO POTENTIAL INCREASES IN LOW CLOUDS AND SHRA
ALONG WINDWARD AND MAUKA REGIONS. AIRMET TANGO WILL CONTINUED TO
BE MONITORED FOR LOW LEVEL TURBULENCE.
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 AND INTO THE
WEEKEND.
A SERIES OF SMALL, MEDIUM PERIOD SOUTH (170-190 DEGREE) SWELLS
ARE EXPECTED THROUGHOUT THE WEEK WITH SURF AROUND THE SUMMER AVERAGE
EXPECTED LATE WEDNESDAY THROUGH AROUND SATURDAY. 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 NEARLY FLAT 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
DURING THE NEXT FEW AFTERNOONS. A COASTAL FLOOD STATEMENT IS IN
EFFECT FOR MINOR COASTAL FLOODING THIS WEEK.
FIRE WEATHER
MODERATE TO LOCALLY BREEZY TRADE WINDS ARE EXPECTED AS HIGH
PRESSURE BUILDS OVER THE STATE. SATELLITE IMAGERY AND LATEST
GUIDANCE SHOWS DIRER AIR FILTERING INTO THE REGION AS INVERSION
HEIGHTS LOWER TO AROUND 5,000 TO 6,000 FEET. DESPITE LOWEST
RELATIVE HUMIDITIES DIPPING AS LOW AS THE MID 40S DURING THE
AFTERNOON HOURS EACH DAY, WIND SPEEDS LOOK TO BE A LIMITING
FACTOR, SO NOT ANTICIPATING ANY FIRE WEATHER HEADLINES AT THIS
TIME.
HFO WATCHES/WARNINGS/ADVISORIES
SMALL CRAFT ADVISORY UNTIL 6 PM HST THURSDAY FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.
DISCUSSION...VAUGHAN
AVIATION...JVC/DT
MARINE...KINO
FIRE WEATHER...VAUGHAN
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