Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
803 AM EDT Sat Mar 14 2015

Valid 00Z Sun Mar 15 2015 - 00Z Sun Mar 22 2015

The majority of guidance offers good agreement for the forecast
pattern over the next seven days.  Brisk north-northeast winds
will gain a little more of an easterly component and start to
slacken a bit this weekend as high pressure to the northwest of
the state begins to weaken and become more elongated.  The surface
ridge should weaken sufficiently to allow for light and variable
winds by next Mon-Tue.  An approaching front will likely reach the
islands around Wed-Thu.  As this front weakens/lifts away,
trailing high pressure should bring a return of brisk
northeasterly winds for late this week into next weekend.  For the
past couple days the models/ensembles have been diverging with
exact timing/amplitude of shortwaves embedded within Pacific flow
aloft.  Low amplitude of the overall mean flow leads to low
confidence in any specific solution aloft but fortunately at the
moment these differences appear to have minimal impact on the
surface pattern.  

Any windward focused showers that occur this weekend should be
light as precipitable water values only increase to just above
0.75 inch by Sun.  PWATs should reach closer to an inch for the
first half of next week with lighter low level winds likely
allowing for more of a sea/land breeze influence on shower
activity.  Expect moisture/rainfall accompanying the weakening
front Wed-Thu to be fairly modest as well with PWATs generally
remaining below 1.25 inches, followed by a return of windward
focus to showers late week into the weekend as trades become
established once again.

Rausch