Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
350 AM EDT Sun Aug 21 2022

Valid 00Z Mon Aug 22 2022 - 00Z Mon Aug 29 2022

Once again, the model/ensemble guidance is similar and consistent
through about the middle of next week and then displays various
trends and differences.  The light and primarily windward-focused
shower pattern supported by below-climatology moisture and
moderate trade flow through the weekend will transition to
somewhat higher rainfall totals and more sea/land breeze influence
by Tuesday-Wednesday as an area of greater moisture crosses the
state while an upper trough and surface front to the north disrupt
the initial surface ridge.  From late week onward, latest guidance
has trended toward the earlier minority ECMWF idea of a
mid-latitude upper low dropping along a path well north/northwest
of the state.  However the current cluster keeps the feature far
enough northwest to allow for somewhat more westward building of
the eastern Pacific surface ridge.  Thus the recently advertised
rebound in trades and renewed windward shower focus late week into
the weekend has oscillated back to being a little stronger.  Today
the one extreme model is the 00Z CMC which ultimately brings the
upper low closer to the islands, thus yielding lighter winds. 
Overall expect moisture to fluctuate during this time frame.  The
ECMWF has finally backed off somewhat from its pocket of moisture
that it wanted to bring through around Friday or so, while by
Sunday the 00Z GFS/GEFS mean and 12Z ECMWF mean all keep moisture
somewhat lower than in the 00Z ECMWF. 

Rausch