HAWAII EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 821 AM EDT FRI JUN 14 2013 VALID 00Z SAT JUN 15 2013 - 00Z SAT JUN 22 2013 14/00Z GFS/ECMWF/CANADIAN GUIDANCE REMAINS IN GOOD AGREEMENT UNTIL DAY 5 (WED). THE GEFS/CANADIAN MEANS BECOME SLIGHTLY FASTER SOLUTIONS ALOFT IN THE NORTHERN PACIFIC AND ALONG THE MAINLAND'S NORTHWEST COAST BY EARLY DAY 7. THE CONSEQUENCE OF THE FASTER SOLUTION IS A SLIGHTLY WEAKER SURFACE RIDGE NORTHEAST OF HAWAII...AND A SLACKENING OF THE TRADES (BY 5 KNOTS) STARTING NEXT WEDNESDAY. BEYOND DAY 5...THE 14/00Z DETERMINISTIC GFS/ECMWF/CANADIAN RUNS STRUGGLE WITH THE BREAKDOWN OF AN ANOMALOUSLY WARM UPPER-LEVEL RIDGE/HIGH ANCHORED OVER ALASKA....AND THE NORTH PACIFIC FLOW PATTERN DEVELOPING OVER THE ALEUTIANS (UNDERNEATH AND UNDERCUTTING THIS RIDGE FROM THE WEST). THE DETERMINISTIC GFS LOOKED LIKE THE OUTLIER OVER THE ALASKAN INTERIOR/NORTH SLOPE BY DAY 7 WITH THE DETERMINISTIC ECMWF AND ITS CUTOFF H5 SOLUTION INVOF 38N176W ON DAY 7 BEING THE OUTLIER IN THE CENTRAL PACIFIC (TO THE NORTHWEST OF KAUAI). THE DETERMINISTIC CANADIAN IS THE SLOWER/DEEPER OUTLIER ACROSS THE ALEUTIANS...BUT A DECENT MIDDLE GROUND ELSEWHERE. GIVEN ALL THE UNCERTAINTY AFTER DAY 5...RECOMMEND A BLEND OF THE 14/00Z BIAS-CORRECTION NAEFS MEAN AND 14/00Z GEFS MEANS FOR THE TROUGH IN THE NORTHERN PACIFIC AND ITS ATTENDANT UPPER-LEVEL TROUGH AXIS EXTENDING SOUTHWARD INTO THE SUBTROPICS. ANTICIPATE...MODERATE TO BRISK TRADES TO CONTINUE ACROSS THE ISLANDS UNTIL MONDAY. NEXT WEEK...A MORE VARIABLE INTENSITY IS SETTING UP WITH TUESDAY/WEDNESDAY BEING THE TRANSITION DAYS (MOST UNCERTAIN PERIOD FOR TIMING THE DECREASE IN TRADEWIND INTENSITIES). CONFIDENCE IS BELOW AVERAGE FOR THURSDAY AND BEYOND REGARDING THE TRADEWIND DISRUPTION . VOJTESAK