056
FXHW60 PHFO 231400
AFDHFO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST SAT AUG 23 2025
SYNOPSIS
THE ISLANDS WILL REMAIN UNDER THE INFLUENCE OF HIGH PRESSURE
RIDGING TO THE NORTH AND EAST WITH A TROUGH LINGERING FAR
NORTHWEST OF THE STATE. THIS WILL RESULT IN CONTINUED LIGHT TO
LOCALLY BREEZY TRADE WINDS THIS WEEKEND. THERE WILL BE A SLIGHT
DROP OFF OF WINDS EARLY NEXT WEEK IN RESPONSE TO THE TROUGH
SLIGHTLY SAGGING SOUTH AND WEAKENING THE DOWNSTREAM PRESSURE
GRADIENT. A DRY AND STABLE WEATHER PATTERN WINS OUT IN THE NEAR
FUTURE WITH ONLY OCCASIONAL LIGHT TRADE SHOWERS WITHIN WINDWARD
MAUKA.
DISCUSSION
THIS AFTERNOON'S SATELLITE IMAGERY SHOWS MOSTLY DRY CONDITIONS
ACROSS THE STATE WITH ONLY A HANDFUL OF RAINFALL STATIONS SHOWING
MEASURABLE PRECIPITATION DURING THE PAST 6 HOURS. AFTERNOON
SOUNDINGS FROM HILO AND LIHUE SHOW A TYPICAL DRY SUMMERTIME
SOUNDING WITH PRECIPITABLE WATER VALUES AROUND 1.2 INCHES AND A
STRONG INVERSION STARTING AT AROUND 5500 FEET.
FOR SATURDAY, WE WILL CONTINUE TO SEE DRY SUMMERTIME CONDITIONS
WITH MODERATE TO LOCALLY BREEZY TRADE WINDS. STARTING SUNDAY, A
TROUGH DEVELOPING NORTH OF THE STATE WILL CAUSE THE RIDGE OF HIGH
PRESSURE TO WEAKEN AND WILL LIKELY CAUSE THE WINDS TO DECREASE
AND VEER TOWARD THE EAST-SOUTHEAST THROUGH MONDAY. BESIDES THE
WINDS VEERING TOWARDS THE EAST-SOUTHEAST AND DECREASING A TOUCH ON
SUNDAY, THE OVERALL THEME WILL CONTINUE WITH MOSTLY DRY CONDITIONS
EXPECTED ON SUNDAY. ALTHOUGH WITH THE WINDS WEAKENING SOME, WE
COULD SEE MORE AREAS WITH SEA BREEZES DURING THE DAY SUNDAY AND
MONDAY, WHICH COULD BRING SOME AFTERNOON CLOUD COVER FOR SELECT
LEEWARD AREAS.
BY TUESDAY, WE SHOULD SEE THE TROUGH LIFT NORTHWARD AND AWAY FROM
THE STATE AND A NEW HIGH WILL BE BUILDING FAR NORTH OF THE STATE.
THIS SHOULD BRING THE RETURN OF OUR TYPICAL BREEZY TRADE WINDS. AS
OUR BREEZY TRADE WINDS RETURN, WE COULD SEE A SLIGHT INCREASE OF
SOME WINDWARD SHOWERS, BUT OVERALL NO SIGNIFICANT PRECIPITATION IS
EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
AVIATION
MODERATE TO BREEZY EASTERLY TRADE WINDS WILL PERSIST THROUGH THE
FORECAST PERIOD. CLOUDS AND SHOWERS WILL REMAIN PRIMARILY FOCUSED
TO THE WINDWARD MAUKA SLOPES, PARTICULARLY DURING THE NOCTURNAL
HOURS. BRIEF MVFR CONDITIONS WILL BE POSSIBLE WITHIN HEAVIER SHOWERS,
OTHERWISE VFR WILL LIKELY PREVAIL.
NO AIRMETS ARE CURRENTLY IN EFFECT.
MARINE
A HIGH PRESSURE RIDGE NORTH OF THE HAWAIIAN ISLANDS CONTINUES TO
PRODUCE FRESH TO LOCALLY STRONG TRADES THROUGH EARLY NEXT WEEK. A
SMALL CRAFT ADVISORY (SCA) REMAINS IN EFFECT FOR THE WINDIER
WATERS OF MAUI COUNTY AND THE BIG ISLAND. THIS SCA WILL LIKELY
CONTINUE INTO THE FIRST HALF OF NEXT WEEK.
SMALL OVERLAPPING MEDIUM AND LONG PERIOD SOUTH SWELLS WILL CONTINUE
TODAY, THIS SWELL ENERGY WILL FADE INTO BACKGROUND LEVELS BY
SUNDAY. SURF HEIGHTS WILL CONTINUE TO DECLINE INTO MONDAY.
ANOTHER SMALL LONG PERIOD SOUTH SWELL WILL ARRIVE BY TUESDAY,
BOOSTING SOUTH SHORE SURF HEIGHTS THROUGH THURSDAY.
SURF ALONG NORTH AND WEST FACING SHORES REMAINS NEARLY FLAT. WHILE
SMALL TRADE WIND DRIVEN WAVE CHOP LINGERS OUT EAST.
FIRE WEATHER
THE LACK OF RAIN AND LOWER HUMIDITY WILL MAINTAIN ELEVATED FIRE
WEATHER CONCERNS THIS WEEKEND. OTHER THAN THE TYPICAL HIGH TERRAIN
CHANNELED WINDS, MANY LOCATIONS WILL EXPERIENCE LIGHT TO LOW END
MODERATE TRADES OR AFTERNOON SEA BREEZES/OVERNIGHT LAND BREEZES.
WHILE MANY WILL EXPERIENCE AFTERNOON HUMIDITIES FALLING UNDER 50
PERCENT, LIGHTER WINDS SHOULD HOLD RED FLAG WARNING (RFW) CONDITIONS
AT BAY. THESE DRY CONDITIONS HAVE PLACED THE MAJORITY OF THE
STATE IN A MODERATE TO SEVERE DROUGHT. THUS, REGIONAL SCALE WINDS
WILL NEED TO BE THE PARAMETER THAT IS MOST CLOSELY MONITORED IN A
POTENTIAL RFW SITUATION. INVERSION HEIGHTS WILL UNDERGO LITTLE
CHANGE SO THE MAIN DRIVER OF WIND WILL BE SUPPORTED IN THE LARGE
SCALE. WIND SPEEDS ARE EXPECTED TO FALL OFF EARLY NEXT WEEK IN
RESPONSE TO A NORTHERN TROUGH WEAKENING THE GRADIENT PRODUCED BY
EASTERN HIGH PRESSURE. AS THIS TROUGH PULLS BACK FURTHER NORTH AT
MID WEEK, TRADES MAY SLIGHTLY INCREASE TO MORE TYPICAL MODERATE
SPEEDS WEDNESDAY.
HFO WATCHES/WARNINGS/ADVISORIES
SMALL CRAFT ADVISORY UNTIL 6 PM HST SUNDAY FOR MAALAEA BAY-
PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.
DISCUSSION...BLOOD
AVIATION...BLOOD
MARINE...BOHLIN
FIRE WEATHER...BLOOD
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