Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
713 AM EST Mon Jan 25 2016

Valid 00Z Tue Jan 26 2016 - 00Z Tue Feb 02 2016

Model/ensemble guidance still shows reasonably good agreement with
the forecast for the next seven days.  There will be a brief
period of enhanced winds from the north/northeast just behind a
front currently passing through the islands.  Then from Tue into
Thu the area will be under a surface ridge on the far periphery of
eastern Pacific high pressure, while a wavy front slowly
approaches from the northwest.  This pattern will likely favor
easterly/southeasterly winds near the Big Island and southerly to
southwesterly winds over the northwestern islands.  Small scale
nature of embedded waves reduces confidence in determining a
precise position of the front as it reaches the northwestern
islands late in the week.  Thus would recommend an intermediate
solution where guidance differences exist.  This front should
stall over the islands and gradually dissipate by Sat-Mon as
another front approaches.  Sun-Mon may feature more typical trade
flow with high pressure passing to the north of the islands.

Highest precipitable water values during the period should exceed
1.25 inches in a narrow band along the front initially crossing
the area.  Otherwise expect PWATs generally on either side of an
inch and occasionally closer to 0.75 inch.  Expect shower activity
to be lighter/more scattered than average with focus dependent on
the low level wind regime in place at the time.  Northwestern
islands could see modestly higher rainfall near the slow moving
wavy front later in the week into the weekend.

Rausch