Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
327 AM EST Sun Jan 12 2020

Valid 00Z Mon Jan 13 2020 - 00Z Mon Jan 20 2020

...Heavy rainfall pattern for Hawaii this week...

A favored composite of reasonably well clustered model and
ensemble forecasts holds a ridge to the north of the state over
the next few days as vort energy lingers over the islands in a
pattern with brisk lower level trades. A low that has solidified
west of the islands will meanwhile lift northward away from the
state as trough/low energies dig near the dateline, but overall
slow pattern progression should allow deepened moisture to linger
over the islands. This would fuel an ongoing threat of locally
heavy rain, especially over favored windward terrain as trades
gradually trend from easterly to southeasterly. The weakening of
the high to the north and frontal approach from the northwest
should allow for island trades to slacken through mid-late week.
Frontal approach may meanwhile act to refocus the slow moving
channel of lead moisture into the state prior to a possible drying
trend into next weekend with system/flow progression.

Flash flood watches and/or flood advisories are currently in place
statewide, with flash flood warnings now in effect for the eastern
Big Island. Cooled temperatures aloft have prompted winter storm
warnings for Mauna Loa and Mauna Kea. Small craft and high surf
advisories along with offshore gale watch/warnings are also in
effect. Please refer to the latest products from NWS WFO Honolulu
for updated information.

Schichtel