Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
246 AM EDT Sat Oct 17 2020

Valid 00Z Sun Oct 18 2020 - 00Z Sun Oct 25 2020

...Heavy Rainfall Threat for Hawaii...

Persistence of an amplified upper low/trough to the northwest of
the state through early next week will work/stall a lead front
into the state. Disrupted trades/land-sea flow and deep moisture
pooling with precipitable water values upwards of 1.75-2" centered
into the west-central islands will be available to fuel a
multi-day period with a threat for locally heavy rains with
runoff/flooding potential. Model and ensemble solutions remain
well clustered, again bolstering forecast confidence. Expected
upper low/trough ejection and the gradual diminishing of the front
and moisture plume starting next midweek would gradually weaken
heavy rainfall support. In this transition, trades may gradually
return into later next week and offer some potential to bring
tropical moisture into the islands from the southeast. 

Schichtel