Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
429 PM EDT Tue Mar 27 2018

Valid 12Z Sat Mar 31 2018 - 12Z Wed Apr 04 2018

The latest model and ensemble guidance continues to struggle with
individual shortwaves embedded within the blocking pattern over
the Bering Sea and North Pacific Ocean. These differences in
timing and placement persist through the extended periods and
result in a lower than desired forecast confidence- the largest
being the evolution of the shortwave moving from the Bering Sea
across southwestern mainland Alaska.

The GFS has continued the trend consolidating the energy into an
upper low over the eastern Gulf while and the ECMWF/CMC showing
the wave interacting with additional Arctic energy as the Bering
ridge builds, resulting in a cutoff low that drifts westward
toward the Aleutians. Given these widely differing solutions
throughout the medium range period, opted to keep any changes very
limited. Therefore choose a blend of the previous forecast, 00Z
ensemble means and 06Z operational GFS.

In terms of sensible weather, rising heights over the state will
result in a warming trend into the weekend and also drier air.
Depending on if or how the trough evolves over the eastern Gulf,
temperatures will start to cool for the beginning of next week.
The greatest potential for precipitation will be for northern
portions of Alaska this weekend and then drifting southward toward
the panhandle on Monday and Tuesday.

Campbell