Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
729 AM EST Sun Feb 24 2019

Valid 00Z Mon Feb 25 2019 - 00Z Mon Mar 04 2019

With the strong ridging stretching into Alaska, this will favor
lower heights to its south, roughly along 150W to the northeast of
Hawai'i next week. A mid-level trough is digging southward toward
Hawai'i and is expected to pinch off into a closed mid-level low
later today. At the surface, the tail-end of a front will continue
pushing southeast away from the islands. Drier air is expected to
return today which will keep shower activity to a
minimum--although the Big Island could have remnant showers
through late tonight. The next cold front follows quickly, pushing
through the northern islands tonight and will bring modest
precipitable water values--increasing chances for showers.

On Tuesday and into Wednesday, guidance shows another mid-level
low pinching off and pushing south toward Hawai'i. This will keep
higher precipitable water values in place as another frontal
boundary pushes across the island chain. By Thursday, this system
progresses eastward along with the frontal boundary. Northwest to
north winds will increase behind this front, with drier air once
again settling over the area. Ensembles continue to show yet
another mid-level low dipping southward by Sunday morning. the 00Z
CMC ensemble mean/00Z ECMWF ensemble mean show this low to be a
bit faster than the 06Z GEFS mean/00Z NAEFS mean. However, all are
in agreement of this feature being in place by Sunday--suggesting
another round of showers will be possible.


Reinhart/Fracasso