Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
725 AM EST Sat Nov 22 2014

Valid 00Z Sun Nov 23 2014 - 00Z Sun Nov 30 2014

The 22/00Z ECENS/GEFS and their deterministic runs appeared to
hold decent continuity through the day3-day3.5 time frame. This
forecast cycle---the GFS offered a more consistent approach
regarding the downstream east central Pacific pattern and evolving
scenario versus the ECMWF. The mid-latitude frontal passage
remains on target for a 24/12Z-25/12Z arrival/departure time
respectively and a notable wind shift and temperature/dew point
change is in the offing. Still some differences with the possible
post-frontal ---shear-line--- pattern for the Islands. The
deterministic 22/00Z ECMWF looked more ominous/pessimistic versus
the GFS---due to its much deeper surface wave development
northeast of Hawai'i.

Thought that holding on to either of these two deterministic
solutions beyond day 3.5 may end up producing opposing conclusions
in the subtropical central Pacific by day5. And beyond day5, with
the character of migratory surface high pressure building across
the western subtropical Pacific.

Some of the differences 'crop-up' as the post-frontal surface wave
migrates towards the Mainland. And other differences emerge at
high latitude---over the Aleutians and Bering Sea. Overall, I
thought the 00Z ECMWF looked like a bad run over more of the
northern hemisphere than is normally the case. It looks nothing
like its ECENS mean in various parts of the Pacific Rim.

Believe a blend the 22/00Z GEFS/ECENS means will easily handle the
mass fields for Hawai'i for the latter half of next week (day
5-7).  

Vojtesak