Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
743 AM EDT Sun Mar 20 2016

Valid 00Z Mon Mar 21 2016 - 00Z Mon Mar 28 2016

The model guidance shows excellent agreement with the Pacific
anticyclone north of Hawai'i moving east to be located northeast
of the islands, with winds veering to become east and then east
southeast by mid week.  Showers are primarily expected in coastal
areas where northeast flow comes onshore and in windward terrain.
Coverage is expected to be sparse early this week given below
normal precipitable water values.

The anticyclone moves east with time, so by mid week the high is
well northeast of the islands, and a front slowly approaches from
the west. Moisture pooling along the front results in precipitable
water values reversing to above normal values by Wednesday, with
frontal lift providing enhanced chances of showers/thunderstorms
at the end of the week into next weekend.  With the frontal
passage, drier air is expected to return towards the end of next
weekend into early next week.

The models/ensembles are in better agreement today on the timing
of the frontal arrival and departure, with the twist of several
waves of low pressure may develop along the front to enhance
shower/storm coverage/amounts that will get resolved in real time.

Petersen