Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
717 AM EST Thu Mar 02 2017

Valid 00Z Fri Mar 03 2017 - 00Z Fri Mar 10 2017

Expect a decrease in rainfall over the next couple days as the
vigorous system that had been affecting the state continues to
lift northward and a weak surface ridge builds in from the east. 
There may still be enough moist southerly flow to promote
scattered light activity though.  Guidance still agrees upon a
weakening front reaching the islands during the weekend with
mostly light to moderate rainfall.  Then models and ensemble means
continue to differ on significant details of the forecast.  So far
each day different solutions have strayed from consensus/average
in different ways for the upper trough evolving to the northwest
of the islands during the first half of the week.  This has led to
significant differences in position of the leading surface front
and potentially moderate/heavy rainfall.  Today the 00z ECMWF/CMC
become more progressive with the upper trough leading to the front
and heavier rainfall extending farther eastward into the islands,
while the slower GFS/GEFS would affect mainly the northwestern
islands.  Since the 06z/01 cycle the GFS/GEFS runs have been
showing much earlier phasing of higher latitude flow with the
central Pacific trough versus other guidance.  On the other hand a
majority of the 00z EC/CMC ensemble members recommend slower
progression than their operational counterparts.  These
considerations and the daily variability of guidance favor a
compromise timing of the upper trough and surface front/rainfall
through next Thursday.

Rausch