Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
321 AM EST Mon Feb 24 2020

Valid 00Z Tue Feb 25 2020 - 00Z Tue Mar 03 2020

...Heavy rain possible for the Big Island this coming weekend into
next week...


A surface front will stall/dissipate near Kauai on Tuesday.
Generally light showers are expected as precipitable water values
fluctuate around an inch and upper heights rise. Troughing to the
east of the region will drift northeastward but another piece will
dig southward just to the east of the Big Island late Fri into
Sat. The models/ensembles generally stall this upper low near the
Big Island into next week thought the 00Z ECMWF takes it westward
past 160W by late next Mon. Prefer to stay near the ensemble
consensus which was just west of the 00Z GFS/Canadian but east of
the 00Z ECMWF. This position would help to draw in higher
precipitable water values to at least the Big Island next weekend
and then possibly through the rest of the islands into next week.
This could lead to an increase in showers and locally heavy
rainfall over at least the Big Island. The modestly tight pressure
gradient (1035mb high near 37N/157W 12Z Fri) will support elevated
trades for much of the week with mainly light/modest showers until
the weekend.


Fracasso