Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
756 PM EDT Tue Sep 28 2021
Valid 12Z Sat Oct 02 2021 - 12Z Wed Oct 06 2021
...Pattern Overview and Guidance/Predictability Assessment...
An active weather pattern can be expected during the extended
forecast period across the Alaska domain with two large storm
systems. The first will be over the northern Gulf and peaking in
intensity Friday night and into early Saturday before steadily
weakening through the remainder of the weekend. The second system
will be the extratropical version of what is now Typhoon Mindulle
and this is forecast to cross the Bering early next week, with a
narrow ridge axis between these two storm systems.
Model guidance is initially well clustered with the Gulf system
for the weekend, and a general deterministic blend would suffice
here. For the Bering Sea system early next week, the ECMWF/ECENS
is actually more progressive than the GFS/GEFS, with the CMC
slightly farther south with the low track.
...Weather/Hazard Highlights...
A vigorous storm system digging through the eastern Bering Sea
this week will slam into a highly unsettled Gulf of Alaska Friday
and the weekend to present a substantial maritime threat for high
waves/winds along with heavy rain/snow for especially coastal
areas of south-central Alaska through the Southeast Panhandle with
moistening onshore flow. Meanwhile, A deep extratropical low
associated with current west Pacific Typhoon Mindulle is slated to
track toward the southern Bering Sea and Aleutians by early next
week to present another significant heavy seas/wind and wrapping
rainfall threat.
Hamrick
Hazards:
- Heavy precipitation across portions of the Alaska Panhandle and
mainland Alaska, Fri-Sat, Oct 1-Oct 2.
- High winds across portions of the Alaska Panhandle and mainland
Alaska, Fri-Sat, Oct 1-Oct 2.
- High winds across portions of the Aleutians, Mon-Tue, Oct 4-Oct
5.
Additional 3-7 Day Hazard Information can be found on the WPC
medium range hazards outlook 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