Prognostic Meteorological Discussion
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FXHW01 KWNH 271229
PMDHI

HAWAII EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
828 AM EDT MON JUL 27 2015

VALID 00Z TUE JUL 28 2015 - 00Z TUE AUG 04 2015

SHORT-TERM MODEL FORECASTS LOOKED SOLID ACROSS PACIFIC THROUGH DAY
3. THE 27/00Z CYCLE STILL HAS SOME UNRESOLVED DETAILS CONCERNING
THE EXCHANGE OF MOISTURE AND ENERGY BETWEEN THE MID-LATITUDE FLOW
AND SUBTROPICS---BUT FOR THE MOST PART THESE DIFFERENCES ARE
ANCHORED ALONG 140W AND 170E---BOOKENDING THE ISLANDS AND ALLOWING
A `FAIRLY PERSISTENCE-BASED` FORECAST THROUGH DAY 6.

EXTENDED FORECAST IN THE TROPICS---
THROUGH DAY 5---THE 27/00Z DETERMINISTIC GFS/ECMWF/CANADIAN AND
ECENS/GEFS SUPPORT A SOLID CONSENSUS FOR THE ORGANIZING TROPICAL
DISTURBANCE ---CURRENTLY INVOF 15N 175E--- TO MAKE A PASS ACROSS
THE MARIANAS AROUND THE 2/12Z TIME FRAME. THE CANADIAN IS ON THE
FAST SIDE OF THE ENSEMBLE ENVELOPE, THE GFS ON THE SLOWER SIDE,
AND THE ECMWF IN THE MIDDLE---BUT A SLIGHTLY FASTER SOLUTION
VERSUS ITS 27/00Z ECENS MEAN.

A VERY BROAD REGION OF DISTURBED WEATHER EMBEDDED WITHIN AN
UNUSUALLY ACTIVE FAR SOUTHEASTERN PACIFIC MONSOON
TROUGH/ITCZ---CURRENTLY MIGRATING A SERIES OF TROPICAL IMPULSES
WESTWARD ALONG 10N FROM THE COAST OF COLOMBIA (80W LONGITUDE) TO
HAWAI`I (160W LONGITUDE). FROM THIS TROPICAL REGION, THE
DETERMINISTIC AND ENSEMBLE GUIDANCE PROJECTS SOME UNSETTLED
WEATHER TO PERIODICALLY MOVE CLOSER TO THE BIG ISLAND. FOR A THIRD
SET OF 00Z FORECAST CYCLES---THE ECMWF HAS MAINTAINED THE BEST
CONTINUITY WITH THE MIGRATION OF A DISTURBANCE WEST OF 145W ALONG
15N. THE 27/00Z GFS HAS `IDENTIFIED IT` NEAR 14N 151W AT 3/12Z AND
THE ECMWF CARRIES THIS DISTURBANCE NEAR 14.5N 144W VALID AT 3/12Z.
THE CANADIAN SEEMS TO BE AN OUTLIER SOLUTION HERE.  PLEASE REFER
TO THE NATIONAL HURRICANE CENTER (NHC) FOR ADDITIONAL DETAILS
REGARDING THIS BROAD AREA OF DISTURBED WEATHER.

VOJTESAK

$$





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