Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
346 AM EDT Mon Sep 26 2022

Valid 00Z Tue Sep 27 2022 - 00Z Tue Oct 04 2022

There are no major changes in the latest guidance for the forecast
covering the next seven days.  Expect generally easterly but
fairly light trades during the first part of the week as a front
settles just north of the state, leading to a combination of
windward/mountain focus and sea breeze influence for showers
depending on location.  Trades should become somewhat stronger
with better defined windward/mountain emphasis after midweek.  The
initial front to the north will weaken, and while another front
may drop nearly as far south during the weekend, there should be
sufficient mid-latitude Pacific high pressure to its north to
maintain at least moderate trades into early next week.  Note that
recent CMC runs have been extreme relative to other guidance in
having an upper low drop to a position northeast of the state,
ultimately disrupting the surface pattern by Sunday-Monday. 
Preference sides with the GFS/ECMWF and their means.

Meanwhile the ensemble means maintain a general east-west axis of
mostly below-climatology precipitable water values that should be
most persistent over the southeast half of the main islands. 
Northwestern areas may be in the southern periphery of the
moisture associated with each of the two fronts to the north. 
Confidence is fairly low in the specifics of any transient pockets
of enhanced moisture carried by the trades, with guidance signals
fading a bit compared to 24 hours ago for one such band around
Thursday-Friday and GFS/ECMWF runs varying with some details
thereafter.  Continue to expect mostly light rain overall but the
possibility for locally enhanced totals depending on moisture
specifics and any small-scale/low-predictability upper level
impulses by the weekend and early next week.

Rausch