073  
FXHW60 PHFO 091320  
AFDHFO  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE HONOLULU HI  
320 AM HST WED JUL 9 2025  
   
SYNOPSIS  
 
AN AREA OF STRONG HIGH PRESSURE WILL BEGIN TO WEAKEN AND LIFT  
NORTHEAST OF THE ISLANDS TODAY. TRADES WILL WEAKEN SLIGHTLY AS A  
RESULT OF THE EASED PRESSURE GRADIENT. EXPECT PASSING SHOWERS  
ENCAPSULATED WITHIN A BAND OF FAIRLY STABLE CLOUDS TODAY, LEADING  
UP TO MORE TYPICAL TRADE SHOWER ACTIVITY FOR WINDWARD AND MAUKA  
AREAS FOR THE REMAINDER OF THE WEEK.  
 
 
   
DISCUSSION  
 
AN AREA OF STRONG HIGH PRESSURE RESPONSIBLE FOR MAINTAINING  
BREEZY TO STRONG TRADES WILL BEGIN TO WEAKEN AND LIFT  
NORTHEASTWARD, EASING THE LOCAL PRESSURE GRADIENT. AS A RESULT,  
TRADES WILL SLIGHTLY WEAKEN THROUGH THE REMAINDER OF THE WEEK.  
WHILE TRENDS ARE SHOWING WEAKENING, BRIEF PERIODS OF STRONGER  
WINDS MAY STILL REMAIN IN WIND-PRONE LOCATIONS. HOWEVER, LATEST  
OBSERVATIONS, INCLUDING ACROSS THE SUMMITS, HAVE BEGUN TO SHOW  
THIS DECREASE, AS OVERALL TRADES ARE EXPECTED TO BE MODERATE TO  
LOCALLY BREEZY BEGINNING TODAY.  
 
AS TRADES WEAKEN, FIRE CONCERNS WILL ALSO BE ON THE DECLINE.  
EXPECT HUMIDITY LEVELS REBOUND BACK ABOVE CRITERIA LEVELS AND THE  
LOCAL KBDI VALUE AT HONOLULU REMAINS BELOW THE 600 THRESHOLD.  
WHILE CONDITIONS ARE NOT FAVORABLE FOR FIRE CONCERNS, IT IS WORTH  
NOTING THAT ANY UNINTENTIONAL SPARK COULD LEAD TO A FIRE AND TO  
REMAIN VIGILANT WHEN RECREATING OUTDOORS DURING THIS TRANSITION  
PERIOD.  
 
LATEST SATELLITE OBSERVATIONS ALSO SHOWCASE SOME PASSING SHOWERS  
ENCAPSULATED WITHIN A BAND OF FAIRLY STABLE CLOUDS MOVING WEST TO  
EAST INTO THE WINDWARD AND MAUKA AREAS. POCKETS OF MOISTURE WILL  
LIKELY BE ESCORTED BY THESE TRADES, BRINGING PERIODIC SHOWER  
ACTIVITY TO WINDWARD AND MAUKA AREAS THROUGH THE REMAINDER OF THE  
WEEK.  
 
 
   
AVIATION  
 
MODERATE TO LOCALLY BREEZY TRADES PERSIST THROUGH THE DAY UNDER  
PREDOMINATELY STABLE CONDITIONS. PASSING SHOWERS FAVORING  
WINDWARD AND MOUNTAIN AREAS MAY LEAD TO BRIEF MVFR CONDITIONS.  
OTHERWISE, VFR CONDITIONS WILL PREVAIL.  
 
AIRMET TANGO REMAINS IN EFFECT FOR MODERATE LOW-LEVEL TURBULENCE  
OVER AND DOWNWIND OF ISLAND TERRAIN.  
 
 
   
MARINE  
 
HIGH PRESSURE FAR NORTHEAST OF THE ISLANDS WILL SUPPORT FRESH TO  
STRONG TRADES ACROSS THE AREA. A SMALL CRAFT ADVISORY (SCA) IS NOW  
IN EFFECT FOR ALL HAWAIIAN COASTAL WATERS THROUGH 6 AM HST WEDNESDAY.  
THE SURFACE HIGH WILL MOVE EASTWARD AND WEAKEN SLIGHTLY DURING THE  
SECOND HALF OF THE WEEK, BUT WINDS ARE LIKELY TO REMAIN BREEZY TO  
LOCALLY STRONG IN THE WINDIER CHANNELS AND WATERS OF MAUI COUNTY  
AND THE BIG ISLAND THROUGH THE REST OF THE WEEK. A SCA IS IN  
EFFECT FROM 6AM WEDNESDAY THROUGH 6AM THURSDAY FOR THE TYPICAL  
WINDIER WATERS AROUND MAUI AND THE BIG ISLAND.  
 
A SMALL MID-PERIOD SOUTH SWELL WILL CONTINUE THROUGH THURSDAY. A  
SLIGHT BOOST TO THE PERIOD EXPECTED ON SATURDAY. ANOTHER SMALL, LONG-  
PERIOD SWELL EXPECTED NEXT SUNDAY NIGHT INTO MONDAY. SURF ALONG SOUTH  
FACING SHORES WILL BOOST ALONG WITH THE ARRIVAL OF THE MENTIONED  
SWELLS. SURF ALONG EAST-FACING SHORES WILL BE ROUGH AND CHOPPY DUE TO  
THE BREEZY TRADE WINDS THAT WILL PERSIST THE REST OF THE WEEK.  
 
 
   
HFO WATCHES/WARNINGS/ADVISORIES  
 
SMALL CRAFT ADVISORY UNTIL 6 AM HST EARLY THIS MORNING FOR KAUAI  
NORTHWEST WATERS-KAUAI WINDWARD WATERS-KAUAI LEEWARD WATERS-  
KAUAI CHANNEL-OAHU WINDWARD WATERS-OAHU LEEWARD WATERS-KAIWI  
CHANNEL-MAUI COUNTY WINDWARD WATERS-MAUI COUNTY LEEWARD 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...PIERCE  
AVIATION...PIERCE  
MARINE...WALSH  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab HI Page
Main Text Page