Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
730 AM EST Mon Feb 11 2019

Valid 00Z Tue Feb 12 2019 - 00Z Tue Feb 19 2019

...Unusually Deep Storm with Strong/Damaging Winds and High Waves
near Hawaii...

A major gale passing just to the north of Hawaii dug far south to
near 22.5N 156W with a surface pressure of 999 mb at 06 UTC as per
Ocean Prediction Center analysis. Water vapor imagery shows a
double barreled closed low aloft with a potent southern
circulation supporting the system. The storm's extreme combination
of depth and southward extent is offering 500mb/850mb heights 4-6
standard deviations below normal as was expected. Please consult
your NWS Honolulu Weather Forecast Office for the latest watches
and warnings.

The main low will remain a significant maritime threat as it
ejects to the northeast of the state over the next couple of days.
Meanwhile, a favored composite of reasonably well clustered model
and ensemble guidance indicates that unsettled weather will remain
over the islands the rest of the week into next week as
reinforcing energy/height falls rotate back over the state into a
lingering upper trough/closed low position. Midweek deeper
moisture pooling is expected to increase shower activity over the
islands, but precipitatble water values decrease thereafter in a
pattern transitioning to cool and brisk post-frontal northeasterly
trades. In this pattern, there will remain potential for daily
windward showers/summit snows and maritime/coastal hazards as
potent high pressure builds and settles to the northeast of the
state.

Schichtel