Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
350 AM EDT Wed Apr 19 2023

Valid 00Z Thu Apr 20 2023 - 00Z Thu Apr 27 2023

The energetic front initially bringing heavy rainfall and strong
southerly winds will gradually trend weaker as it pushes eastward.
 By Thursday the Big Island could still see some locally heavy
rainfall but likely with lighter totals than over areas farther
west, especially with recent trends that take the axis of greatest
moisture a little farther east of the Big Island.  With the front
weakening further late in the week, what moisture remains should
return back to the northwest from Friday into the weekend as
easterly to southeasterly trades develop.  Then another central
Pacific system will bring a front toward the islands by Sunday or
Monday, with the front likely settling over the state through
midweek.  There is better than average agreement for this front
given the 5-7 day time frame, and latest GFS runs have finally
adjusted toward other guidance that has been keeping the
supporting upper low a lot farther away from the state than a
number of earlier GFS runs.  This front will lead to another
disruption in trades, with winds turning northerly to
northeasterly behind it.  Guidance is consistent in showing steady
to declining precipitable water values along the front early-mid
week, suggesting rainfall in the lighter half of the spectrum.

Rausch