The Weather Prediction Center

College Park, MD

Hawaii Extended Forecast Discussion

Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
823 AM EDT Sun Oct 22 2017

Valid 00Z Mon Oct 23 2017 - 00Z Mon Oct 30 2017

...Heavy rain threat late Monday through Tuesday...

East southeast trades will continue to veer to the southeast and
then south ahead of an approaching cold front late Monday through
Tuesday from NW to SE across the island chain. This is in response
to a forming upper low near 30N/160W early Tuesday that is
forecast to remain quasi-stationary for about 24 hours and then
lift to the northeast on Wednesday. Deep tropical moisture should
be drawn northward ahead of the front into the region on Tuesday
-- precipitable water values rising to near 2 inches or +2 to +4
standard deviations -- which supports a heavy rain threat for at
least 24 hours. The consensus takes the front just east of the Big
Island late Wednesday into Thursday, bringing in cooler and much
drier air on NW flow to the state. For next Fri-Sun, winds will
continue to veer to the N then NE and eventually ENE by the end of
next weekend but remain rather breezy.


Last Updated: 823 AM EDT Sun Oct 22 2017