196
FXHW60 PHFO 121928
AFDHFO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
928 AM HST TUE MAY 12 2026
SYNOPSIS
BREEZY TRADE WINDS WILL CONTINUE THROUGH MOST OF THE WEEK.
SHOWERS WILL FAVOR WINDWARD AND MAUKA AREAS, MOST FREQUENTLY AT
NIGHT AND DURING THE EARLY MORNING HOURS. LATE THIS WEEK INTO THE
WEEKEND, AN UPPER-LEVEL DISTURBANCE MAY BRING A SLIGHT UPTICK IN
TRADE WIND SHOWER COVERAGE.
SHORT TERM UPDATE
ISSUED AT 928 AM HST TUE MAY 12 2026
THE ONLY MINOR CHANGE WITH THIS MID MORNING UPDATE IS TO MENTION
THAT THE WEAK SURFACE TROUGH JUST TO THE NORTH OF THE STATE
REFERENCED EARLIER THIS MORNING HAS DISSIPATED. HOWEVER, REMNANT
MOISTURE IN THE VICINITY OF THIS DISSIPATED BOUNDARY WILL
CONTINUE TO SUPPLY LOW-LEVEL CLOUDS AND SHOWERS TO KAUAI THROUGH
THE DAY AS IT IS TRANSPORTED IN ON THE BREEZY TRADE WIND FLOW.
RADAR AND SATELLITE IMAGERY ALSO SHOW LOW-LEVEL CLOUDS AND SHOWERS
MOVING INTO WINDWARD AREAS OF THE BIG ISLAND. OTHERWISE, DRIER
AIR IS FILTERING INTO THE CENTRAL PART OF THE STATE WITH ONLY THE
OCCASIONAL ISOLATED SHOWER MOVING THROUGH.
WITH HIGH PRESSURE TO THE NORTH DOMINATING, TYPICAL BREEZY
TRADE WIND WEATHER WILL PERSIST, WITH CLOUDS AND SHOWERS FAVORING
WINDWARD AND MAUKA AREAS THROUGH AT LEAST MIDWEEK.
PREV DISCUSSION
ISSUED AT 350 AM HST TUE MAY 12 2026
EARLY THIS MORNING, SATELLITE AND RADAR IMAGERY CONTINUES TO SHOW
LOW CLOUDS AND SHOWERS UPSTREAM OF KAUAI EMBEDDED WITHIN THE
TRADE WIND FLOW APPROACHING AND MOVING OVER THE GARDEN ISLE AS A
WEAK SURFACE TROUGH CONTINUES TO LINGER NEAR THE WESTERN END OF
THE STATE. THIS TROUGH HAS SUPPORTED MORE WIDESPREAD CLOUD
COVERAGE AND NUMEROUS SHOWERS OVER KAUAI AND ITS ADJACENT WATERS
THROUGHOUT THE NIGHT, A TREND THAT WILL CONTINUE THROUGHOUT THE
DAY. ELSEWHERE, SHOWERS AND LOW CLOUDS EMBEDDED WITHIN THE
MODERATE TO LOCALLY BREEZY TRADE WIND FLOW MOVING INTO PRIMARILY
WINDWARD AND MAUKA SECTIONS OF THE ISLANDS HAVE BEEN MORE ISOLATED
TO SCATTERED IN NATURE.
THE WEAK TROUGH NEAR THE WESTERN END OF THE STATE IS FORECAST TO
GRADUALLY LIFT NORTH AND DISSIPATE BY WEDNESDAY. OTHERWISE,
RIDGING AT THE SURFACE AND ALOFT WILL MAINTAIN STABLE, BREEZY
TRADE WIND WEATHER ACROSS THE STATE THROUGH AT LEAST THURSDAY WITH
ISOLATED TO SCATTERED SHOWERS FAVORING WINDWARD AND MAUKA AREAS.
NEAR THE END OF THE WEEK (FRIDAY INTO THE WEEKEND), CONFIDENCE IN
THE FORECAST DECREASES A BIT AS MODEL GUIDANCE DIVERGES. WHILE THE
CONSENSUS IS THAT THAT A MID- TO UPPER- LEVEL CUTOFF LOW WILL
DEVELOP IN THE VICINITY OF THE ISLANDS, THERE ARE SOME SIGNIFICANT
DIFFERENCES AMONG THE GLOBAL MODELS AS TO THE LOCATION OF THIS
FEATURE (FOR EXAMPLE, THE ECMWF DEPICTS IT WELL NORTHEAST OF THE
ISLANDS WHILE THE GFS PLACES IT VERY CLOSE TO, OR EVEN JUST WEST
OF, KAUAI). REGARDLESS, INSTABILITY LOOKS TO INCREASE AS
TEMPERATURES ALOFT COOL, POTENTIALLY INCREASING TRADE WIND SHOWER
ACTIVITY TO END THE WEEK.
AVIATION
ISSUED AT 928 AM HST TUE MAY 12 2026
HIGH PRESSURE FAR NORTH OF THE ISLANDS WILL MAINTAIN A BREEZY
TRADE WIND PATTERN OVER THE REGIONS OVER THE NEXT SEVERAL DAYS.
MID-LEVEL RIDGING WILL HELP TO LIMIT SHOWER ACTIVITY WITH A STABLE
AIRMASS IN PLACE.
LIMITED SHOWERS BEING CARRIED IN ON THE TRADE WIND FLOW ARE
IMPACTING THE WINDWARD SIDES OF KAUAI AND THE BIG ISLAND. AIRMET
SIERRA IS IN EFFECT FOR MOUNTAIN OBSCURATION ON THE EAST SIDES OF
THOSE ISLANDS AS A RESULT. CONDITIONS ARE LIKELY TO IMPROVE THIS
AFTERNOON, BUT COULD RETURN OVERNIGHT. VFR CONDITIONS ARE EXPECTED
ELSEWHERE.
AIRMET TANGO REMAINS IN EFFECT FOR MECHANICAL TURBULENCE TO THE
LEE OF THE MOUNTAINS DUE TO THE BREEZY TRADE WINDS. EXPECT THIS TO
REMAIN IN PLACE OVER THE NEXT COUPLE OF DAYS. AN ADDITIONAL AIRMET
TANGO HAS BEEN ISSUED FOR UPPER LEVEL TURBULENCE AS THE RESULT OF
AN UPPER LEVEL JET MOVING OVER THE ISLANDS. THIS IS EXPECTED TO
MOVE TO THE EAST OF THE ISLANDS LATE THIS AFTERNOON.
MARINE
ISSUED AT 350 AM HST TUE MAY 12 2026
HIGH PRESSURE REMAINS IN PLACE NORTH OF THE HAWAIIAN ISLANDS INTO
THE FIRST HALF OF NEXT WEEK, KEEPING FRESH TO LOCALLY STRONG
TRADES BLOWING THROUGH THURSDAY. AN UPPER LEVEL DISTURBANCE MOVES
INTO THE HAWAII REGION FROM THE NORTH FROM FRIDAY INTO THE
WEEKEND. EXPECT INCREASING CLOUDS AND SHOWER TRENDS ALONG WITH A
SLIGHT DECREASE IN TRADE WIND SPEEDS AS A LOW LEVEL TROUGH
DEVELOPS OVER THE ISLANDS. THE SMALL CRAFT ADVISORY WAS EXTENDED
THROUGH WEDNESDAY AFTERNOON, AND WILL LIKELY CONTINUE INTO
THURSDAY FOR THE TYPICAL WINDIER WATERS AND CHANNELS NEAR MAUI AND
THE BIG ISLAND.
A SMALL SHORT TO MEDIUM PERIOD NORTHWEST (330 DEG) SWELL WILL
SLOWLY DECREASE THROUGH TONIGHT. THE NEXT SMALL LONG PERIOD
NORTHWEST SWELL ARRIVES INTO THE WESTERN ISLANDS BY WEDNESDAY
AFTERNOON, PEAKING ON THURSDAY, THEN SLOWLY FADING INTO FRIDAY.
EXPECT SMALL SURF TO CONTINUE ALONG NORTH AND WEST FACING SHORES
OF THE WESTERN ISLANDS AT LEAST INTO THURSDAY.
THE SMALL LONG PERIOD SOUTH SWELL ENERGY WILL CONTINUE TO SHOW A
SLOW DECLINE THROUGH THE WEEK WITH THE PERIOD DROPPING BY 1
SECOND EACH DAY. THE NEXT SMALL LONG PERIOD SOUTH SWELL ARRIVES ON
SATURDAY, KEEPING SURF HEIGHTS ELEVATED ALONG SOUTH FACING
SHORES. SLIGHTLY ELEVATED SURF ALONG E FACING SHORES CONTINUES
UNTIL TRADES WEAKEN THIS WEEKEND.
HFO WATCHES/WARNINGS/ADVISORIES
SMALL CRAFT ADVISORY UNTIL 6 PM HST WEDNESDAY FOR ALENUIHAHA
CHANNEL-BIG ISLAND LEEWARD WATERS-BIG ISLAND SOUTHEAST WATERS-
MAALAEA BAY-PAILOLO CHANNEL.
SHORT TERM UPDATE...FARRIS
DISCUSSION...VAUGHAN
AVIATION...M BALLARD
MARINE...BOHLIN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page