Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
823 AM EDT Mon Oct 05 2015

Valid 00Z Tue Oct 06 2015 - 00Z Tue Oct 13 2015

Please refer to the Central Pacific Hurricane Center (CPHC)
concerning "Oho" and it's impacts on Hawai'i.

Medium Range thoughts---
Would suggest a 70/30 blend of the 5/00Z ECENS/GEFS
means---between day 3-7. This will maintain a smooth forecast
across the mid-latitude Pacific, Gulf of Alaska and downstream
across the North American continent. By day 5, the ECENS begins to
carve another mid-level trough out of the deep vortex in the Gulf
of Alaska --- and along 160W while the GEFS starts to flatten the
flow---but maintains a west southwesterly steering flow along 40N.
At this time frame, both are reasonable conclusions west of the
Dateline. The deep low should anchor in the Gulf of Alaska and
await the outcome of "Choi-wan's" entrainment across the
mid-latitude west Pac flow pattern (invof ne Japan).   

The 5/00Z deterministic GFS/ECMWF continues its struggle---beyond
the day 3 time frame---with the moisture/energy transfers between
Tropics and mid latitudes. With the deterministic ECMWF a much
faster solution than the GFS---hard to recommend the extreme ECMWF
solution downstream in the Gulf of Alaska and Panhandle by day 4.
There is too much (separation) with respect to latitude...and too
little connectivity anticipated along 30N 145W to consider the
deterministic ECMWF versus its ECENS mean.

Vojtesak