Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
305 PM EST Wed Jan 09 2019

Valid 12Z Sun Jan 13 2019 - 12Z Thu Jan 17 2019

With a persistent blocking pattern over the Mainland, multiple
occluded systems are anticipated to track across the Aleutian
Chain and Gulf of Alaska which will keep much of the southern
coast/Southeast wet and the Interior mainly dry in the extended
forecast. Additionally, cold air will be entrenched over the
Interior- temperatures will be 15 to 30 degrees colder than
seasonal normal through the end of the week with a slight
improvement by the end of the extended period.

The global models are beginning show clustering early on with the
shortwave energy crossing the Aleutians, however they continue to
diverge by day 5. The ensemble means have be consistent the past
few days on how blocking/trough evolves, therefore for continuity,
the preferred WPC blend was based on a 06Z GFS/00Z ECMWF with a
heavier weighting of the ensemble means.

Campbell


WPC medium range Alaskan products including 500mb, surface
fronts/pressures progs and sensible weather grids can be found at:

http://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif
http://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml
http://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html