Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
655 PM EST Wed Feb 05 2025
Valid 12Z Sun Feb 09 2025 - 12Z Thu Feb 13 2025
...High winds across Aleutians and SW mainland late this weekend
into early next week; heavy precipitation over parts of Alaska
Peninsula...
...Overview...
The upper-level pattern will remain mainly stationary with
troughing over the North Pacific and western Bering as well as
ridging from the Gulf Coast through the mainland. Shortwave energy
will likely propagate along the southern periphery of the trough
through the Aleutians as well as across the Seward Peninsula and
the northern mainland. Deep, occluded low pressure systems are
likely to move across the western and central Aleutians. Surface
high pressure slowly degrades beneath the retreating upper ridge
into western Canada.
...Guidance Evaluation and Preferences...
Both deterministic and ensemble guidance did a fairly good job of
capturing the overall synoptic pattern across the Alaska region
during the Medium Range period. Small details regarding embedded
shortwave energy have yet to be resolved by the guidance, though.
A general model blend consisting of the latest deterministic
ECMWF/GFS/CMC/UKMET were utilized in the blend between days 4 and
5. No one piece of guidance was favored over another due to the
amount of uncertainty present in the guidance. The 06z GEFS and
00z ECENS were introduced to the blend on day 6 and continued
through the end of the period while the 00z CMCE was introduced to
the blend on day 7 and continued through the end of the period.
The deterministic Euro, GFS and CMC were diminished in weighting
through the end of the period.
...Weather/Hazards Highlights...
A deep low pressure system will approach the western Aleutians
from the north Pacific on Superbowl Sunday. A deep, entrenched
area of high pressure across mainland Alaska will promote an
increasing pressure gradient between these two areas of central
pressure. This will result in high winds across the western
Aleutians on Sunday before spreading into the Alaskan Panhandle
and Lower Kuskokwim region on Monday. Heavy rain/snow is likely to
persist across the Panhandle throughout the period due to the
constant troughing and southerly flow into the elevated area.
Temperatures should remain around average for much of the Gulf
Coast and mainland while a warming trend ensues for the Aleutians
and western mainland.
Kebede
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