Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
319 AM EDT Wed Mar 29 2023

Valid 00Z Thu Mar 30 2023 - 00Z Thu Apr 6 2023

A large upper low associated with an intensifying surface low near
30N/170W Wednesday is forecast to slowly meander in place through
the end of the week since it will be cut off from the westerlies,
and then slowly lift north this weekend and finally away from the
northwestern Islands.  The GEFS mean is slightly faster to lift
the low out compared to the ECENS, but otherwise they are in good
agreement.  The central and eastern Islands will continue to be on
the southwestern periphery of the subtropical high through most of
the forecast period, and as the low lifts north well away from the
state, the high then tries to build back westward centered near 35
degrees north, with this being more strongly supported by the GEFS
mean.

It appears the majority of the showers and thunderstorms
associated with the trailing stationary front should remain from
Kauai Island and points west, and mainly terrain enhanced showers
with ESE to SE flow across most of the populated Islands east of
Kauai.  The trades should then become more easterly going into
early next week as the ridge axis builds in to the north, and
perhaps an increase in showers near the Big Island as a weak upper
trough passes through the region.

Hamrick