The Weather Prediction Center

College Park, MD


Hawaii Extended Forecast Discussion




Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
712 AM EST Fri Nov 21 2014

Valid 00Z Sat Nov 22 2014 - 00Z Sat Nov 29 2014

The 21/00Z forecast cycle offered a good depiction of the sensible
weather scenario for Hawai'i through day 4---with more detail on
the next frontal system migrating from the Aleutians to the east
central Pacific by day 5-6.

The 21/00Z ECENS/GEFS were in much better 'synch' with the mass
fields through day 5 and it's the deterministic 21/00Z
GFS-Canadian that have a deeper (closed 500mb low) solution
migrating northeastward into the mid-latitude east Pacific by
26/12Z. The GFS-parallel and ECMWF carry more of a positive-tilt
trough eastward---but essentially, the stalled closed low solution
from yesterday is gone.

And the trend is---a progressive solution for a surface frontal
passage for Monday, more in line with yesterday's GFS
(20/00Z-20/06Z cycles). The frontal passage should alter the
current wind field pattern, and depending on the forward speed of
the exiting trough---the western Islands will likely be affected
by one or more shear lines developing in the wake of the departing
system.

Beyond day 5, a mass-field blend of the 21/00Z GEFS/ECENS means
should handle the timing of heights rises (a migratory upper-level
ridge) moving west to east along 20N latitude.

Vojtesak





Last Updated: 712 AM EST Fri Nov 21 2014