Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
244 AM EST Sun Jan 17 2021

Valid 00Z Mon Jan 18 2021 - 00Z Mon Jan 25 2021

The weather pattern for the beginning of the week is expected to
become more unsettled across the Hawaii domain as a potent upper
level develops, and then evolves into an upper low just south of
the state based on the EC and GEFS means.  This would result in a
noteworthy inverted surface trough and stationary front over the
region.  The ensemble means are indicating that this disturbance
could be in place through at least Wednesday and then slowly
retrograde towards the west and weaken.  Both the GFS and ECMWF
are in better agreement with the axis of heaviest rainfall over
the central and eastern Islands, primarily on Monday and Tuesday.

By the end of the week and into next Saturday, the trough is
expected to dissipate as the surface high builds back in to the
northeast of the state.  This will tend to strengthen the trades
with a mainly easterly component to the flow.

Hamrick