Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
252 AM EST Tue Dec 06 2022

Valid 00Z Wed Dec 07 2022 - 00Z Wed Dec 14 2022

...Kona low development just northwest of the state favors some
heavy rain potential...

The GFS/ECMWF/UKMET/Canadian models and supportive ensembles still
offer a similar pattern evolution for the coming week in an active
pattern with above average predictability. There is a strong
signal to continue the carving out a Kona low today just to the
northwest of the islands that is slated to slowly eject
northwestward away from the state over the next couple of days.
Latest radar and blended TPW loops show that southerly flow into
the islands is bringing a deep plume of tropical moisture into the
western islands, with a secondary plume directed toward the Big
Island. These may fuel some heavy downpours that may lead to local
runoff issues.

High pressure bridging/building strongly in guidance to the
northeast of the state in the wake of closed low departure should
then support a return moderate to breezy easterly trades and
revert to a pattern with more limited moisture and windward
terrain focusing showers under an amplifying upper ridge for much
of the remainder of this forecast period. There is a guidance
signal to monitor that shows separated/closed low energy set to
work southwestard to just southeast of the islands late weekend
into early next week.
 
Schichtel