572  
FXHW01 KWNH 160756  
PMDHI  
 
HAWAII EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
356 AM EDT THU MAY 16 2024  
 
VALID 00Z FRI MAY 17 2024 - 00Z FRI MAY 24 2024  
   
..HEAVY RAIN THREAT LATE WEEK INTO THE WEEKEND
 
 
LATEST GUIDANCE CONTINUES TO INDICATE THAT THE DEEP UPPER LOW  
INITIALLY NORTH-NORTHWEST OF THE STATE AND ASSOCIATED SURFACE  
BOUNDARY REACHING THE MAIN ISLANDS WILL SUPPORT A PERIOD OF HEAVY  
RAINFALL WITH FLASH FLOODING THREATS DRIFTING FROM THE CENTRAL  
ISLANDS INTO THE WESTERN PART OF THE STATE OVER THE COMING DAYS.  
AROUND SUNDAY THERE IS LINGERING UNCERTAINTY IN EXACTLY WHEN THE  
BAND OF HEAVIEST RAINFALL WILL ULTIMATELY REACH WEST OF THE MAIN  
ISLANDS. FROM MONDAY ONWARD EXPECT LIGHT TO MODERATE  
EAST-SOUTHEASTERLY TO SOUTHEASTERLY WINDS WITH A COMBINATION OF  
WINDWARD AND SEA BREEZE FOCUS FOR SHOWERS.  
 
AS FOR DETAILS, THERE IS FAIRLY GOOD CONSENSUS INTO THE FIRST PART  
OF THE WEEKEND FOR THE BEST MOISTURE AXIS AND FOCUSING SURFACE  
BOUNDARY GRADUALLY SHIFTING WESTWARD AS THE UPPER LOW DRIFTS A  
LITTLE FARTHER AWAY TO THE NORTH. SUNDAY IS CURRENTLY MORE OF A  
QUESTION MARK AS SOME GUIDANCE SAYS THE AXIS OF HEAVIEST RAINFALL  
COULD ALREADY REACH JUST WEST OF THE WESTERN ISLANDS, BUT  
CONSENSUS STILL DEPICTS FAIRLY HIGH PRECIPITABLE WATER (PWAT)  
ANOMALIES OVER THE AREA. THE 00Z ECMWF-INITIALIZED MACHINE  
LEARNING MODELS ESSENTIALLY SPLIT THE DIFFERENCE, SHOWING THE AXIS  
OF HIGHEST QPF A LITTLE WEST BUT WITH SOME CONTINUED ENHANCEMENT  
INTO THE STATE THAT WOULD BE CONSISTENT WITH THE HIGH MOISTURE.  
TRADE SHOWERS FROM MONDAY ONWARD SHOULD PRODUCE LIGHTER RAINFALL,  
THOUGH THE COMBINATION OF PWATS STAYING SOMEWHAT ABOVE NORMAL AND  
UPPER LEVEL IMPULSES COULD STILL PROVIDE SOME LOCALIZED  
ENHANCEMENT.  
 
RAUSCH  
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab HPC Page Main Text Page