Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
500 PM EST Fri Jan 03 2020
Valid 12Z Tue Jan 07 2020 - 12Z Sat Jan 11 2020
...Weather/Hazards Highlights...
Upper ridging is forecast to work across the southern Arctic Ocean
early next week and eventually heights rise underneath over the
interior to gradually ease the recent cold snap. Active and fairly
progressive flow cuts underneath into a stormy Bering/Aleutians
and Gulf of Alaska. Models and ensembles continue to struggle with
embedded system timing in the flow, but overall still align
adequately with the larger scale flow evolution. This will carry a
couple areas of low pressure toward and into the Panhandle
early-mid next week. As these systems exit into British Columbia,
the main focus shifts to the Bering Sea as a series of potentially
deep lows with a threat of high winds/waves and heavy
precipitation feed into the region all next week. Renewed lead
triple point low developments meanwhile work downstream into an
unsettled Gulf of Alaska again, with renewed potential into later
next week.
...Guidance/Predictability Assessment...
The 12 UTC GFS/ECMWF/UKMET/Canadian offer embedded system
variance, but seem sufficiently clustered to allow preference for
a blend with the 12 UTC GEFS/NAEFS/ECMWF ensemble means days 4/5
Tue/Wed. Suggest a transition to a more compatable blend of
ensembles by day 7/8 to maintain good WPC continuity along with
the NBM.
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
Hazards:
- Much below normal temperatures for parts of mainland Alaska,
Mon-Tue, Jan 6-Jan 7.
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