Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
816 AM EDT Sat Oct 10 2015

Valid 00Z Sun Oct 11 2015 - 00Z Sun Oct 18 2015

From the weekend into early next week an elongated surface ridge
to the north of the state should support trades in the lighter
half of the spectrum.  For a portion of this time a surface trough
may disrupt trade flow at some locations allowing for greater
land/sea breeze influence on shower activity.  Also during the
weekend a band of enhanced deep moisture as denoted by
precipitable water values of at least 2-2.50 inches, currently
nearing the Big Island, will continue to drift west/northwestward.
 This moisture may help to increase rainfall amounts for a time.

By next Tue-Wed guidance has come into better agreement regarding
the developing east-central Pacific mean trough whose influence
will extend into the islands.  Current consensus is in the middle
to faster half of the prior solution envelope with the initial
trough amplifying to the north of the islands.  This progression
is in response to a rapidly approaching Aleutians upper low that
digs into the mean trough, tracking approximately over 40N 150W. 
The result at the surface will be a frontal passage with trailing
high pressure likely supporting winds of at least moderate
strength from the north or northeast during the latter half of
next week into the weekend.  PWATs should decline somewhat though
still remain high enough to allow for some terrain focused showers.

Rausch