HAWAII EXTENDED FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD 729 AM EST SAT MAR 02 2013 VALID 00Z SUN MAR 03 2013 - 00Z SUN MAR 10 2013 2/00Z GUIDANCE (ECMWF/CANADIAN/GFS) INCLUDING THEIR MEANS WERE IN DECENT AGREEMENT WITH 'BAGGY' TROUGH ALOFT MIGRATING SLOWLY EASTWARD OF 140W THROUGH 7/12Z. THE PROGRESSION OF THIS UPPER-LEVEL FEATURE WILL WORK IN TANDEM WITH THE LOW-LEVEL FLOW...ALLOWING A SURFACE RIDGE TO SLOWLY MIGRATE EASTWARD. THE END RESULT IS A SLACKENING OF THE MODERATE TO BRISK TRADES AROUND MONDAY NIGHT AND TUESDAY. BEYOND 8/00Z...THE MODEL SPREAD ALOFT IN THE NORTH CENTRAL PACIFIC INCREASES. UNCERTAINTY LIES MORE OVER THE WEST COAST OF THE MAINLAND AND OVER THE CENTRAL ALEUTIANS...WHERE MID-LATITUDE NORTHERN STREAM ADJUSTMENTS ARE IN A TRANSITION PERIOD TO MORE OF A SPLIT-FLOW REGIME . FOR THE SUBTROPICS...THE DIFFERENCES ARE LESS OBVIOUS...AND THE MODEL GUIDANCE TRENDS HAVE BEEN TO KEEP A WEAK UPPER-LEVEL LOW/TROUGH TO THE EAST AND SOUTHEAST OF THE ISLAND. GENERALLY SPEAKING...THE TROUGHINESS WOULD HAVE MORE IMPACT ON THE BIG ISLAND WITH RESPECT TO THE AREAL COVERAGE OF SHOWERS...WITH WESTERNMOST LOCALES MUCH DRIER FOR THE FORECAST PERIOD. VOJTESAK