938  
FXHW01 KWNH 290800  
PMDHI  
 
HAWAII EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
259 AM EST TUE NOV 29 2022  
 
VALID 00Z WED NOV 30 2022 - 00Z WED DEC 07 2022  
 
THE AREAS OF HEAVY RAINFALL ASSOCIATED WITH ABUNDANT TROPICAL  
MOISTURE AND SHORTWAVE ENERGY EARLY THIS WEEK SHOULD TAPER OFF  
AFTER TUESDAY AS UPPER HEIGHTS RISE SOMEWHAT. THERE IS STILL A  
REASONABLE CONSENSUS THAT HIGH PRESSURE TO THE DISTANT NORTHEAST  
OF THE STATE WILL PROMOTE A RETURN TO MORE TYPICAL LIGHT/MODERATE  
TRADES AND WINDWARD SHOWER FOCUS LATE THIS WEEK INTO THE WEEKEND.  
HOWEVER, GUIDANCE HAS BEEN STRUGGLING TO DETERMINE THE FINER  
DETAILS OF UPPER RIDGING THAT SHARPENS NEAR 160W LONGITUDE AROUND  
WEDNESDAY-THURSDAY AND GRADUALLY WEAKENS/DRIFTS EASTWARD  
THEREAFTER, ALONG WITH HOW FAR SOUTH/SOUTHWEST INTO THE REGION  
DRIER AIR TO THE NORTH REACHES. AFTER THE WIDELY-VARYING GUIDANCE  
HAD CLUSTERED 24 HOURS AGO TOWARD MORE MOISTURE STAYING OVER THE  
STATE AFTER MIDWEEK, THE MODELS/MEANS NOW CLUSTER JUST AS WELL  
TOWARD A PRONOUNCED DRYING TREND WITH PRECIPITABLE WATER VALUES  
DECLINING TO NEAR AVERAGE FOR A TIME AROUND THE LATE WEEK/EARLY  
WEEKEND TIME FRAME. MOISTURE MAY REBOUND SOMEWHAT AND THE TRADES  
WEAKEN AS A FRONT APPROACHES FROM THE WEST LATE WEEKEND INTO EARLY  
NEXT WEEK. AGAIN BY EARLY NEXT WEEK THERE ARE SOME SIGNIFICANT  
DIFFERENCES FOR HOW SHARPENING SHORTWAVE ENERGY TO THE NORTHWEST  
EVOLVES, LEADING TO ISSUES WITH THE SURFACE FORECAST. THE 00Z  
ECMWF IS MOST AT ODDS WITH MOST OTHER MODELS/MEANS, CLOSING AN  
UPPER LOW JUST WEST OF 170W BY NEXT TUESDAY. THE ASSOCIATED  
SURFACE REFLECTION LEADS TO STRENGTHENING SOUTHEASTERLY WINDS OVER  
THE STATE. REMAINING GUIDANCE STILL DIFFERS AT THE SURFACE AND  
ALOFT BUT OVERALL SUGGESTS MAINTAINING SOME DEGREE OF MORE TYPICAL  
TRADE FLOW, THOUGH POSSIBLY HINDERED BY SURFACE TROUGHING FOR A  
TIME.  
 
RAUSCH  
 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab HPC Page
Main Text Page