Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
300 AM EDT Mon Apr 12 2021

Valid 00Z Tue Apr 13 2021 - 00Z Tue Apr 20 2021

The latest rebound in moisture/instability to fuel some locally
heavy showers/convection should linger today mainly over the
eastern half of the state as shortwave energy rotates down over
the islands on the southwest periphery of a slow moving upper
trough/low settled to the northeast of Hawaii. Shortwave passage
should yield a few days of drier conditions for the islands and a
favored composite of well clustered guidance suggests that ample
mid-latitude upper trough amplification to the north of the state
will meanwhile eject the upper trough/low. Moisture and showers
will increase again late week as flow amplification drives a front
into the state from the north. Post-frontal high pressure building
into the central Pacific may then reinforce trades and a returning
focus for a pattern with some lingering showers over
windward/mountain areas.  

Schichtel