Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
323 PM EDT Sat Oct 26 2019

Valid 12Z Wed Oct 30 2019 - 12Z Sun Nov 03 2019

Upper ridging is forecast to remain just south of the Gulf of
Alaska as ridging moves into the Bering Sea. This will favor
positively-tilted troughing from the North Pacific into
southwestern Alaska and Southcentral.

Models and ensembles show generally good agreement on the longwave
pattern evolution and a blend of the 12Z GFS and 00Z
ECMWF/UKMET/Canadian sufficed to start (with some ensemble
weighting to smooth out some timing differences). Trended to just
a blend of the GFS/ECMWF with their ensemble means by next
weekend. This takes a lead system toward Kodiak early Thursday,
the northern Gulf Friday, and into Canada Saturday. The trailing
front will likely get prevented from moving southward due to the
upper ridging and surface high pressure west of BC/WA. A wave of
low pressure may develop along this front next weekend and move
into the northeastern Gulf, but confidence is low in
timing/strength due to the long lead time. By next weekend, a
system will push into the western Bering as high pressure moves
into western Alaska.

Rain/snow will spread across the AKPEN and Southcentral into
southeastern areas later next week as the front makes steady
progress northeastward then eastward. Precipitation will linger
over the Panhandle with WSW flow aloft and the stationary frontal
boundary. To the north, an old surface low will slowly fill as it
meanders north of Utqiagvik. This may enhance snowfall north of
Kotzebue/Point Hope.

Fracasso


Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards chart at:
<a href="https://www.wpc.ncep.noaa.gov/threats/threats.php"><u>https://www.wpc.ncep.noaa.gov/threats/threats.php</u></a>

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

<a href="https://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif"><u>https://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif</u></a>
<a href="https://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml"><u>https://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml</u></a>
<a href="https://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html"><u>https://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html</u></a>