HAWAII EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
807 AM EDT FRI MAY 17 2013

VALID 00Z SAT MAY 18 2013 - 00Z SAT MAY 25 2013

TRADES WILL RELAX ON SATURDAY AS HIGH PRESSURE PUSHES EASTWARD
PAST 140W. THE MODELS AND ENSEMBLES THEN FORECAST UPPER TROUGHING
TO DIVE SOUTHWARD AND CLOSE OFF AN UPPER LOW NEAR 28N/157W ON
SUNDAY AS A WEAKENING COLD FRONT PUSHES THROUGH THE STATE.
ASSOCIATED SFC LOW SHOULD STAY NORTH OF THE STATE PER THE
GFS/ECMWF AND MOST ENSEMBLES AND THEN SLOWLY DRIFT NORTHWESTWARD
AS HIGH PRESSURE BUILD SOUTHWARD OUT OF THE GULF OF ALASKA. FOR
SUCH AN AMPLIFIED AND RATHER COMPLICATED PATTERN... THE
MODELS/ENSEMBLES SEEMS TO HAVE A GOOD HANDLE OF IT. PW VALUES
SHOULD INCREASE MARKEDLY TO NEAR AND JUST OVER 1.50 IN STATE-WIDE
/ABOUT +2 STD DEV/ BY MONDAY THROUGH THURSDAY FROM SE TO NW AS THE
UPPER LOW RETROGRADES TO THE NW. LOW LEVEL WINDS SHOULD VEER TO
SOUTHEASTERLY THEN SOUTHERLY OVER THE SE ISLANDS WITH TERRAIN AND
SEA-BREEZE ENHANCED PRECIPITATION. WINDS OVER THE NE ISLANDS
SHOULD BACK TO NORTHERLY BEHIND THE SFC TROUGH EARLY IN THE WEEK
BEFORE VEERING TO SOUTHEASTERLY AS THE TROUGH PUSHES
NORTHWESTWARD. GEFS ENSEMBLES FOCUS BEST THE CHANCE FOR RAIN OVER
THE SE ISLANDS THROUGH WEDNESDAY WHILE THE ECMWF ENSEMBLES FOCUS
OVER KAUAI AND OAHU WED-THU... SO SOME DISAGREEMENT REMAINS.


FRACASSO