Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
333 PM EDT Tue Aug 27 2019
Valid 12Z Sat Aug 31 2019 - 12Z Wed Sep 04 2019
The latest mdels and ensembles now more strongly agree that a
potent low pressure system will lift across the Aleutians and
through the eastern Bering Sea late Saturday into early next week
as upper ridging over the eastern mainland slips eastward into
Canada. A composite solution primarily derived from the well
clustered latest GFS/ECMWF and GEFS/ECMWF ensembles was used for
the period from this weekend and Monday. Forecast spread increases
by day 7/8, suggesting usage of just the more compatable ensemble
means at these longer time frames. This system now seems likely to
be a hazard for maritime interests and a downstream heavy
weather/precipitation threat across the Aleutians and
western/southwestern to southern Alaska considering moisture
influx and dynamic support.
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
- Heavy rain over portions of mainland Alaska and the Aleutians,
Sun-Tue, Sep 1-Sep 3.
- High winds over portions of mainland Alaska and the Aleutians,
Sun, Sep 1.
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