Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
630 PM EDT Thu Jun 10 2021
Valid 12Z Mon Jun 14 2021 - 12Z Fri Jun 18 2021
...Guidance/Predictability Evaluation...
The WPC Alaskan medium range product suite was primarily derived
from a blend of reasonably well clustered guidance of the 12 UTC
GFS/ECMWF, 12 UTC GEFS/ECMWF ensemble means and the 19 UTC
National Blend of Models days 4-8 (Monday-next Friday). Applied
manual adjustments and transitioned base forecast blend weighting
from the models toward the ensemble means over time consistent
with a pattern with slowly growing forecast spread and uncertainty
in an effort to maintain max WPC product continuity.
...Weather/Threats Highlights...
Lingering upper troughing from western to northern Alaska may
support some organized frontal precipitation early-mid next week,
with scattered activity inland over parts of the Interior.
Meanwhile, ample southern branch upper troughing will progress
just south of the Aleutians and lows/frontal systems will focus
unsettled weather across the region and downstream across the Gulf
of Alaska, extending into later next week. Additional and
potentially energetic closed trough/low energies with wrapping
rains in this stream are slated to work back to/south of the
Aleutians mid-later next week.
Schichtel
Hazards:
No significant hazards are expected over Alaska during this
forecast period.
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
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