Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
304 AM EST Sat Jan 16 2021

Valid 00Z Sun Jan 17 2021 - 00Z Sun Jan 24 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, and potentially closed low, develops.  This would result in
a noteworthy inverted surface trough and well developed cold front
over the region.  The ensemble means are indicating that this
disturbance could be in place through at least Wednesday and
perhaps into Thursday.  Similar to yesterday, the GFS indicates
that the best tropical moisture surge would likely be east of the
Big Island, whilst the ECMWF is a little farther to the west and
thus more impactful, with periods of heavy rainfall across the
state. 

By the end of the weekend 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