Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
612 PM EDT Fri Apr 08 2022
Valid 12Z Tue Apr 12 2022 - 12Z Sat Apr 16 2022
...Pattern and Weather/Hazard Highlights...
Through the course of the extended period a there will be a ridge
expanding into the Mainland that becomes blocked as multiple low
pressure systems moderately develop on the periphery, near the
Aleutians/Bering and western Canada. This pattern will be
conducive for warmer and drier conditions for most locations;
which will limit or negate any potential hazardous conditions
statewide. 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 latest guidance continues to show minor variances in the
depth, timing and placements of the individual systems that
develop; however, overall the clustering is above average for most
of the extended period. As previously noted, the global guidance
has a better handle on the depth and definition of various
features through about day 6 but higher weighting of the
deterministic guidance over the ensemble means was utilized for
days 7 and 8 than usual-roughly 70/30 by the end. A combination of
the 12Z ECWMF, GFS, CMC and UKMET yielded an acceptable solution
and stayed close to continuity from the previous forecast.
Campbell
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