Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
318 PM EDT Wed May 08 2019
Valid 12Z Sun May 12 2019 - 12Z Thu May 16 2019
Guidance holds a generally blocky flow pattern into next week as
highlighted aloft by a closed/high amplitude and
unsettling/precipitation focusing Bering Sea trough. This feature
extends over the Aleutians to the north Pacific and the Gulf of
Alaska, with a resultant high amplitude ridge downstream from the
northeast Pacific to southeast/eastern Alaska. Latest models and
ensembles are much less progressive and more stream separate
compared to yesterdays runs day 6-8 flow to the south of the
state. This would suggest some potential pattern transition as
increasing energy infuses from the north-central Pacific to the
Gulf of Alaska. This seems to favor offshore storm developments
and maritime risks, albeit with details to become clearer at
shorter time frames.
Model and ensemble forecasts cluster better now into day 4/Sunday
and a composite solution offers reasonable continuity. Guidance
solutions then diverge quickly next week. Accordingly, the WPC
Alaskan medium range product suite was primarily derived from a
blend of more compatable guidance from the 12 UTC GEFS mean and 00
UTC ECMWF ensemble mean, with smaller model and National Blend of
Model inputs.
Schichtel
Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php
No significant hazards are expected over Alaska during this
forecast period.
WPC medium range Alaskan products including 500mb, surface
fronts/pressures progs and sensible weather grids can also be
found at:
https://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml
https://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html