Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
626 PM EST Wed Feb 15 2023
Valid 12Z Sun Feb 19 2023 - 12Z Thu Feb 23 2023
...Model Guidance/Predictability Assessment...
Central Pacific dynamic trends in satellite loops seem to favor a
solution closest to the 12 UTC GFS for Alaska valid Sunday with
associated system tracks into the state on the deeper side of the
full envelope of solutions. Otherwise, the 12 UTC
GFS/ECMWF/Canadian and GEFS/ECMWF ensemble means offer a similar
larger scale pattern evolution that reasonably amplifies and slows
significantly next week. The WPC Alaskan medium range product
suite was primarilty derived from a guidance composite for days
5-8 (Monday-next Thursday) in a pattern with near/above average
predictability. This overall provides good WPC product continuity.
...Pattern Overview and Weather/Hazard Highlights...
The next in a series of lead systems is expected to track into
Southwest Alaska into Sunday as supporting energy transfers
downstream into the northern Gulf of Alaska in progressive flow.
Expect a moderate swath of wintry weather across the Southwest,
the southern Interior and South-central. Enhanced precipitation
will meanwhile develop and linger early next week into Southeast
Alaska with northern Gulf system genesis and departure. This will
lead into a cold and windy pattern with enhanced gap winds for the
rest of next week as upper trough energies to surface flow
response dig earnestly through the region.
Upstream, upper-level systems from the northwest Pacific will
include a series of closed lows that are slated to lift over the
western Bering Sea next week and provide a protracted maritime
threat. In this pattern, a downstream upper ridge will build
significantly up over the mainland. With deepened low pressure
systems over the Bering, wrapped enhanced winds and moderate
precipitation will periodically develop through the period up
through the western periphery of the upper ridge, but eastward
progression will be slow. This activity will spread and focus
across the Aleutians and Bering Sea/maritime interests, then
eventually into western/southwestern AK and the AKpen/vicinity
into mid-later next week.
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