Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
622 PM EDT Thu Apr 07 2022
Valid 12Z Mon Apr 11 2022 - 12Z Fri Apr 15 2022
...Pattern and Weather/Hazard Highlights...
A main Bering Sea upper ridge this weekend remains slated to build
inland and settle over the mainland by early next week, setting
the stage for development of an increasingly blocky pattern around
Alaska that may characteristically linger through much of next
week. Multiple low pressure systems are set to moderately develop
on the periphery of the warming/stabilizing upper ridge in a
pattern with overall limited significant hazards potential over
the state. Precipitation should be limited over the state during
this medium range forecast period in this scenario due to the
shielding/blocky upper ridge, with modest activity mainly to focus
with energies digging southward through the North Slope and
eastern Interior/Gulf of Alaska and more earnestly with a
prolonged and deep layered low position near the Aleutians next
week.
...Guidance/Predictability Assessment...
The decently clustered 12 UTC models show better developed troughs
around the building mainland upper ridge than the ensemble means
into Day 4/5 (Mon/Tue), better in line with a developing Omega
block pattern and a GFS/ECMWF/UKMET/Canadian composite seems to
offer wanted detail compared to the ensemble means. Embedded
system amplitude/timing differences do remain at both lower and
higher latitudes, but forecast spread has improved a bit from
yesterday. The 12 UTC ECMWF does seem to be the model of the day
weakening the block too rapidly into days 7/8 (yesterday it was
the GFS), so for that period today prefer a solution with mainly a
combo of the compatible 12 UTC GEFS/ECMWF ensemble means for run
to run stability and the 12 UTC GFS/Canadian models (with
relatively smaller applied weights) to keep better system
amplitudes consistent with overall pattern trends in a pattern
with near average predictability.
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 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