Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
251 AM EST Thu Dec 28 2023

Valid 00Z Fri Dec 29 2023 - 00Z Fri Jan 05 2024

Today's guidance still shows a pattern featuring a succession of
fronts that will affect the state to varying degrees.  One period
of typical trade flow should be late this week into the weekend as
a dissipating front (or at least its moisture band) settles near
the Big Island by Friday and a trailing front stays well north of
the island--with the latest GFS finally completing its multi-day
northward trend to consensus.  The next front pushing into the
state will briefly disrupt the trades around Sunday-early Monday
and then trailing high pressure will maintain moderate to brisk
trades into midweek.  Then yet another front approaching from the
northwest by next Thursday may shift winds a little more
southeasterly.  Most shower activity with these features should be
in the light to moderate range given precipitable water values
tending to stay below climatology.  At least on a relative basis,
rainfall may increase somewhat over the eastern islands
early-middle of next week.  Based on latest improved guidance
clustering (still minus the CMC), this would be aided by a narrow
axis of shortwave energy separating from the westerlies and
aligning over or near the Big Island, stalling the front over the
area and increasing moisture somewhat.  The front next Thursday
could ultimately lead into a somewhat wetter pattern late next
week as guidance starts to develop a supporting upper trough west
of the state.  The 00Z CMC/CMCens mean are most amplified with
this trough while the 00Z GFS/ECMWF are a middle ground between
the CMC and the flatter GEFS/ECens means.

Rausch