191  
FXHW60 PHFO 071646 CCA  
AFDHFO  
 
AREA FORECAST DISCUSSION...CORRECTED  
NATIONAL WEATHER SERVICE HONOLULU HI  
646 AM HST MON SEP 7 2026  
   
SYNOPSIS
 
 
TRADE WINDS WILL VEER TO THE EAST-SOUTHEAST AND STRENGTHEN AS  
HURRICANE LOWELL APPROACHES. LOWELL IS FORECAST TO PASS WEST OF  
OF KAUAI TONIGHT, BUT CLOSE ENOUGH THAT A HURRICANE WARNING IS IN  
EFFECT FOR KAUAI AND NIIHAU. HIGH SURF AND HEAVY RAIN WILL IMPACT  
ALL ISLANDS WITH STRONG WINDS MAINLY IMPACTING THE WESTERN END OF  
THE STATE.  
 

 
   
DISCUSSION
 
 
HURRICANE LOWELL IS ABOUT 375 MILES SOUTHWEST OF KAUAI THIS  
MORNING MOVING NORTH NORTHEASTWARD. LOWELL'S TRACK HAS SHIFTED  
EASTWARD CLOSER TO KAUAI AND NIIHAU WITH ADVISORY UPDATES  
OVERNIGHT, AND THE CORE OF LOWELL IS EXPECTED TO PASS WEST OF THE  
KAUAI. THIS HAS AGAIN HAS RAISED THE POSSIBILITY OF HURRICANE  
FORCE WINDS REACHING KAUAI AND NIIHAU, AS A RESULT A HURRICANE  
WARNING HAS BEEN ISSUED FOR BOTH ISLANDS. A TROPICAL STORM WATCH  
HAS ALSO BEEN ISSUED FOR OAHU ALSO DUE TO THIS EASTWARD SHIFT.  
 
ADDITIONAL IMPACTS FROM LOWELL ARE EXPECTED STATEWIDE, AND A FEW  
HEADLINES ARE IN EFFECT AS A RESULT. A HIGH SURF WARNING FOR SOUTH  
FACING SHORES FOR THE SOUTH SWELL GENERATED BY LOWELL FOR ALL  
ISLANDS, ALONG WITH THE WEST FACING SHORES OF THE BIG ISLAND. A  
HIGH SURF ADVISORY REMAINS IN EFFECT FOR THE EAST SWELL GENERATED  
BY FORMER TROPICAL STORM KARINA, WHICH HAS WEAKENED TO A POST  
TROPICAL LOW. FOR SURF AND OTHER MARINE IMPACTS, PLEASE SEE THE  
MARINE SECTION OF THE DISCUSSION BELOW.  
 
THE FLOOD WATCH FOR THE STATE CONTINUES THROUGH TUESDAY DUE TO  
HEAVY RAIN BROUGHT IN BY LOWELL AND ASSOCIATED RAIN AND  
THUNDERSTORM BANDS. TERRAIN INFLUENCE WILL PLAY A BIG FACTOR WITH  
ISOLATED AREAS RECEIVING SIGNIFICANT AMOUNTS THROUGH THE EVENT.  
STAY ALERT FOR THE ISSUANCE OF ANY FUTURE FLOOD ADVISORIES OR  
WARNINGS ACROSS THE STATE. SEE HYDROLOGY SECTION FOR ADDITIONAL  
INFORMATION.  
 
THE THREAT OF SHORT-LIVED, FAST-MOVING TORNADOS/WATERSPOUTS WILL  
BE PRESENT MAINLY NEAR KAUAI AND NIIHAU AS LOWELL MAKES ITS  
CLOSEST APPROACH TO THE ISLANDS. THESE WOULD LIKELY BE EMBEDDED IN  
RAINBANDS. THE THREAT FOR TORNADOES IS LOWER NEAR THE REMAINING  
ISLANDS, BUT NOT ZERO. THE THREAT FOR TORNADOES SHOULD DECREASE  
QUICKLY EARLY TUESDAY MORNING.  
 
ANY DEVIATION IN TRACK OR INTENSITY COULD ALSO CHANGE HOW THESE  
HAZARDS EFFECT THE ISLANDS.  
 
HIGH PRESSURE IS FORECAST TO BUILD BACK IN THURSDAY THROUGH  
SATURDAY, BRINGING IN A MORE TYPICAL TRADE WIND PATTERN WITH A  
DRIER AND MORE STABLE AIRMASS.  
 

 
   
AVIATION
 
 
HURRICANE LOWELL CONTINUES ITS TRACK NORTHWARD, ADVECTING UNSTABLE  
DEEP TROPICAL MOISTURE NORTHWARD INTO THE ISLANDS. SHOWER  
ACTIVITY WILL CONTINUE TO TREND HIGHER INTO TUESDAY. MVFR  
CONDITIONS WITH LOW CLOUD CEILINGS AND SHOWERS ARE EXPECTED  
STATEWIDE. HEAVIER SHOWERS WILL PRODUCE PERIODS OF IFR  
CONDITIONS. SURFACE WINDS WILL STRENGTHEN TODAY OVER THE WESTERN  
HALF OF THE STATE, AS HURRICANE LOWELL CONTINUES ON A NORTHERN  
TRACK.  
 
AIRMET SIERRA FOR MOUNTAIN OBSCURATION CONTINUES FOR KAUAI OAHU  
MOLOKAI MAUI AND THE BIG ISLAND. THIS AIRMET WILL LIKELY CONTINUE  
INTO TUESDAY.  
 
AIRMET TANGO WAS ISSUED FOR MODERATE LOW LEVEL TURBULENCE  
AFFECTING THE ISLAND OF KAUAI OVER AND SW THRU NW OF ISLAND  
MOUNTAINS. A STRONG SURFACE WIND AIRMET WILL LIKELY BE ISSUED FOR  
KAUAI AND NIIHAU LATER TODAY FOR WIND SPEEDS GREATER THAN 30  
KNOTS DUE TO HURRICANE LOWELL APPROACHING THE ISLANDS.  
 
LIGHT ICING CONTINUES IN A LAYER BETWEEN 160 AND FL220 DUE TO  
STRENGTHENING LOW LEVEL WIND SPEEDS AS LOWELL APPROACHES THE  
ISLAND.  
 

 
   
MARINE
 
 
HURRICANE LOWELL, LOCATED SOUTHWEST OF THE ISLANDS, CONTINUES TO  
MOVE NORTH-NORTHEAST THIS MORNING. AS IT APPROACHES THE ISLAND  
CHAIN WIND SPEEDS WILL INCREASE. A HURRICANE WARNING REMAINS IN  
EFFECT FOR WATERS WEST OF KAUAI COUNTY, WHILE A TROPICAL STORM  
WARNING REMAINS IN EFFECT FOR KAUAI CHANNEL AND KAUAI WINDWARD  
WATERS THROUGH TUESDAY AFTERNOON. A SLIGHT EASTWARD SHIFT IN THE  
TRACK HAS ALSO PROMPTED THE ISSUANCE OF TROPICAL STORM WATCHES FOR  
OAHU LEEWARD AND WINDWARD WATERS. THE SMALL CRAFT ADVISORY  
REMAINS IN EFFECT FOR ALL REMAINING COASTAL WATERS FOR A  
COMBINATION OF WINDS AND SEAS THROUGH TUESDAY. WINDS ARE EXPECTED  
TO INCREASINGLY VEER TO THE SOUTHEAST TO SOUTH AS LOWELL  
APPROACHES AND THE STRONGEST WINDS AND HIGHEST SEAS ARE EXPECTED  
FOR THE WESTERN END OF THE STATE.  
 
HURRICANE CONDITIONS ARE EXPECTED IN THE WESTERN OFFSHORE WATERS  
AS LOWELL THROUGH TUESDAY AS THE CENTER OF THE STORM TRACKS JUST  
WEST OF NIIHAU. ANY SLIGHT DEVIATION IN THE TRACK TO THE WEST OR  
EAST IN THE NEXT 24 HOURS WILL HAVE SIGNIFICANT DIFFERENCES IN  
IMPACT FOR THE COASTAL WATERS AROUND KAUAI COUNTY. POST-TROPICAL  
CYCLONE KARINA TO THE NORTHEAST OF THE ISLANDS WILL CONTINUE TO  
WEAKEN AND DISSIPATE LATER TODAY.  
 
SOUTH-SOUTHWEST SWELL FROM HURRICANE LOWELL WILL RAPIDLY BUILD TODAY.  
AS A RESULT, SURF ALONG SOUTH FACING SHORES WILL BEGIN TO RISE FROM  
ADVISORY LEVELS THIS MORNING TO WARNING LEVELS BY THIS AFTERNOON AND  
PEAK OVERNIGHT. THE SWELL WILL INCREASINGLY SHIFT OUT OF THE  
SOUTHWEST TONIGHT. DUE TO THE TRACK OF LOWELL WEST OF THE MAIN  
ISLANDS, A SHARP GRADIENT IN SWELL IS EXPECTED FROM WEST TO EAST. THIS  
WILL BRING DAMAGING SURF TO PORTIONS OF KAUAI COUNTY AND POSSIBLY  
OAHU. COINCIDING ALSO WITH THE PEAK MONTHLY AFTERNOON HIGH TIDES,  
THIS COULD BRING THE POTENTIAL FOR SIGNIFICANT DAMAGE TO COASTAL  
PROPERTIES AND INFRASTRUCTURE, INCLUDING ROADWAYS TO PORTIONS OF  
KAUAI AND POSSIBLY OAHU. SWELL ENERGY IS EXPECTED TO RAPIDLY  
DECLINE ON TUESDAY.  
 
A MODERATE, LONG-PERIOD SOUTH SWELL ALSO ARRIVES TODAY AND PEAKS  
OVERNIGHT INTO TUESDAY, BUT WILL BE OVERWHELMED BY THE LARGER  
SWELL FROM HURRICANE LOWELL. ALTHOUGH IT BEGINS TO FADE ON  
TUESDAY, IT WILL KEEP SOUTH SHORE SURF SOMEWHAT ELEVATED THROUGH  
THURSDAY. A LARGE, MEDIUM-PERIOD EAST SWELL FROM FORMER TROPICAL  
STORM KARINA WILL COMBINE WITH INCREASING EAST TO SOUTHEAST WIND  
WAVE GENERATED BY HURRICANE LOWELL TO KEEP ADVISORY LEVEL SURF  
ALONG EAST FACING SHORES THROUGH TUESDAY. SURF ALONG NORTH FACING  
SHORES WILL ALSO EXPERIENCE A SMALL INCREASE ON TUESDAY AS LOWELL  
LIFTS NORTH OF THE ISLAND CHAIN AND THEN FADE THROUGH THE WEEK.  
 

 
   
FIRE WEATHER
 
 
FIRE WEATHER RISK WILL REMAIN LOW THROUGH THE FORECAST PERIOD DUE  
TO INCREASING MOISTURE MOVING OVER THE ISLANDS IN ASSOCIATION  
WITH HURRICANE LOWELL. THUNDERSTORMS WILL BE POSSIBLE THROUGH  
THROUGH TONIGHT TO THE UNSTABLE AIRMASS MOVING OVERHEAD.  
TEMPERATURE INVERSION HEIGHTS ARE EXPECTED TO REMAIN ELEVATED OR  
NON-EXISTENT DURING THE NEXT FEW DAYS.  
 

 
   
HYDROLOGY
 
 
THE POTENTIAL FOR FLOODING EXISTS THROUGH TUESDAY, AND AS A  
RESULT, A FLOOD WATCH IS IN EFFECT FOR THE ENTIRE STATE. IT IS  
POSSIBLE THE WATCH MAY NEED TO BE EXTENDED INTO TUESDAY NIGHT OR  
WEDNESDAY DEPENDING ON THE LINGERING RAIN BANDS ACROSS THE STATE  
IN THE WAKE OF LOWELL AS GUIDANCE SUGGESTS. HOWEVER, WILL HOLD OFF  
ANY UPDATE TO THE WATCH AT THIS TIME.  
 
HURRICANE LOWELL IS EXPECTED TO BRING ADDITIONAL RAIN TO THE  
ISLANDS THROUGH WEDNESDAY MORNING WITH 6 TO 10 INCHES, ISOLATED  
16 INCHES ACROSS KAUAI. OAHU AND MAUI COUNTY, 4 TO 8 INCHES,  
ISOLATED 10 INCHES. BIG ISLAND, 4 TO 8 INCHES, ISOLATED 12 INCHES.  
THIS RAINFALL MAY PRODUCE SIGNIFICANT FLASH FLOODING AND  
MUDSLIDES, ESPECIALLY ACROSS KAUAI COUNTY AND SOUTH AND EAST  
PORTIONS OF THE BIG ISLAND.  
 

 
   
HFO WATCHES/WARNINGS/ADVISORIES
 
 
FLOOD WATCH THROUGH TUESDAY AFTERNOON FOR ALL HAWAII ISLANDS-  
 
HIGH SURF WARNING UNTIL 6 PM HST TUESDAY FOR NIIHAU-KAUAI  
LEEWARD-WAIANAE COAST-KAHOOLAWE-MAUI LEEWARD WEST-KONA-KOHALA-  
KAUAI SOUTH-EAST HONOLULU-HONOLULU METRO-EWA PLAIN-MOLOKAI  
SOUTHEAST-MOLOKAI WEST-MOLOKAI LEEWARD SOUTH-LANAI LEEWARD-LANAI  
SOUTH-MAUI CENTRAL VALLEY SOUTH-KIPAHULU-SOUTH MAUI/UPCOUNTRY-  
SOUTH HALEAKALA-BIG ISLAND SOUTH-BIG ISLAND SOUTHEAST.  
 
HIGH SURF ADVISORY UNTIL 6 PM HST TUESDAY FOR OLOMANA-KAUAI EAST-  
KOOLAU WINDWARD-MOLOKAI WINDWARD-WINDWARD HALEAKALA-BIG ISLAND  
EAST-BIG ISLAND NORTH.  
 
HURRICANE WARNING FOR NIIHAU-KAUAI-  
 
TROPICAL STORM WATCH FOR OAHU-  
 
HURRICANE WARNING FOR KAUAI NORTHWEST WATERS-KAUAI LEEWARD  
WATERS.  
 
TROPICAL STORM WARNING FOR KAUAI WINDWARD WATERS-KAUAI CHANNEL-  
OAHU WINDWARD WATERS-OAHU LEEWARD WATERS.  
 
SMALL CRAFT ADVISORY UNTIL 6 PM HST TUESDAY FOR KAIWI CHANNEL-  
MAUI COUNTY WINDWARD WATERS-MAUI COUNTY LEEWARD WATERS-MAALAEA  
BAY-PAILOLO CHANNEL-ALENUIHAHA CHANNEL-BIG ISLAND WINDWARD  
WATERS-BIG ISLAND LEEWARD WATERS-BIG ISLAND SOUTHEAST WATERS.  
 

 
 

 
 
DISCUSSION/FIRE WEATHER/HYDROLOGY...FOSTER  
AVIATION...BOHLIN  
MARINE...QUESADA  
 
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