Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
839 AM EDT Tue Oct 08 2019

Valid 00Z Wed Oct 09 2019 - 00Z Wed Oct 16 2019

The model guidance is in pretty good agreement over the course of
the next week depicting a subtropical high aloft passing north of
Hawaii from east to west.  Meanwhile, moisture from a couple of
tropical waves will begin to head toward Hawaii as an upper-level
low is forecast to develop to the northwest of the island chain. 
This pattern will guild moisture from the tropical waves gradually
across much of Hawaii from east to west during the latter part of
this week into the weekend.  Meanwhile, wind directions will
slowly veer from easterly to east-southeasterly as a high pressure
ridge in the lower levels builds in from the east.  Precipitable
water values of over 2 inches are forecast to reach the Big Island
on Thursday, then overspread the remainder of state on Friday. 
This will favor a higher chance of heavy rainfall along the east-
and southeast-facing slopes, especially for the Big Island.  The
main moisture axis should be pushing off to the west of the main
islands on Saturday.  By Sunday, drier air from the surface ridge
should be overspreading much of Hawaii.  The drier conditions
should persist through next Tuesday.

Kong