Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 714 AM EST Thu Nov 27 2014 Valid 00Z Fri Nov 28 2014 - 00Z Fri Dec 05 2014 From now through about Mon a general blend of model/ensemble guidance should provide a reasonable starting point for the forecast given fairly minor differences at the surface and aloft. During this period high pressure well north of the islands will support fairly brisk trades, though with a gradual slackening trend as the high weakens and tracks eastward. Expect windward-favored showers to be on the light side with precipitable water values near or below an inch over central/northern islands, and even the Big Island by Sun-Mon. The forecast becomes more uncertain by Tue-Thu as differences aloft affect the surface gradient as well as how much moisture increases over the islands. Given typical guidance errors in the days 5-7 time frame, a compromise between the 00z GEFS and ECMWF ensemble means should provide the most moderate solution with respect to the timing/shape of shortwave energy aloft, degree of increase in deep moisture, and the strength of the surface gradient/trades. Rausch