261  
FXHW01 KWNH 300749  
PMDHI  
 
HAWAII EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
249 AM EST MON JAN 30 2023  
 
VALID 00Z TUE JAN 31 2023 - 00Z TUE FEB 07 2023  
 
HEAVY RAIN AND THUNDERSTORMS ARE LIKELY TO CONTINUE ACROSS HAWAII  
THROUGH AT LEAST TODAY, AS A CLOSED LOW JUST WEST KAUAI WILL  
REMAIN IN PLACE AND CONTINUE TO DRAW IN DEEP TROPICAL MOISTURE AS  
WELL AS PROVIDE INSTABILITY WITH A REMOVED INVERSION GIVEN THE  
LOWERING HEIGHTS ALOFT. MOISTURE LEVELS WILL BE QUITE HIGH WITH  
PRECIPITABLE WATER VALUES LIKELY TO REMAIN OVER THE 90TH, EVEN  
95TH, PERCENTILE. MEANWHILE A SURFACE TROUGH WILL CONTINUE TO  
FOCUS THIS MOISTURE AND GRADUALLY DRIFT WEST OVER THE NEXT COUPLE  
DAYS. ALL ISLANDS MAY BE AT RISK OF SEEING VERY HEAVY RAIN AMOUNTS  
AND ADDITIONAL INSTANCES OF FLOODING--OVER THE EASTERN ISLANDS  
WHERE MOISTURE LEVELS ARE MAXIMIZED AND THE WESTERN ISLANDS  
PARTICULARLY AS THE TROUGH PASSES OVER. THUS THE HONOLULU FORECAST  
OFFICE HAS A FLASH FLOOD WATCH IN PLACE FOR MUCH OF THE STATE.  
ADDITIONALLY, THE SUMMITS OF MAUNA KEA AND MAUNA LOA COULD SEE  
SOME ADDITIONAL SNOW GIVEN THE LOWER HEIGHTS OF THE TROUGH/LOW  
CAUSING COLDER AIR IN THESE HIGHEST ELEVATIONS, AND WINTER STORM  
WARNINGS REMAIN IN EFFECT.  
 
BY TUESDAY AND BEYOND, MODELS GENERALLY INDICATE THAT THE CLOSED  
UPPER LOW SHOULD DRIFT A BIT WEST AWAY FROM THE STATE BUT BE SLOW  
TO ERODE. THIS WILL LEAD TO LESS SUPPORT FOR THE HEAVIEST RAINFALL  
AMOUNTS, BUT ABOVE AVERAGE MOISTURE LOOKS TO STAY IN PLACE THROUGH  
MIDWEEK AND BEYOND, BUT LIKELY TO A LESSER EXTENT. AFTER A PERIOD  
OF SOME WEAKER OVERALL WINDS AROUND MIDWEEK, THE SURFACE PATTERN  
LOOKS FAVORABLE FOR MORE TYPICAL EASTERLY WINDS TO FORM BY LATER  
IN THE WEEK WITH A HIGH TO THE NORTH. ADDITIONALLY, A COLD FRONT  
OR TWO MAY APPROACH HAWAII AND HELP FOCUS MOISTURE, BUT WITH SOME  
UNCERTAINTY IN TIMING AND WITH HOW FAR THE FRONTS SINK SOUTH.  
OVERALL A WET TRADE WIND PATTERN LOOKS TO BE IN STORE THROUGH THE  
REST OF THE WEEK.  
 
TATE  
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab HPC Page Main Text Page