Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
655 PM EST Thu Feb 1 2024
Valid 12Z Mon Feb 5 2024 - 12Z Fri Feb 9 2024
***Bitterly cold temperatures to linger over the eastern Interior
through this weekend***
...Overview...
A deep upper low will affect much of the Aleutians and the Bering
into early next week with increased prospects for precipitation
and gusty winds for portions of the Aleutians and the Alaska
Peninsula. Brutally cold conditions over the weekend are forecast
to improve going into next week as the deep upper trough departs
and broad upper ridging tries to build northward across some of
the mainland from the Gulf region. Most of the Interior should
remain mostly dry.
...Guidance Evaluation/Preferences...
The 12Z model guidance suite, along with the 18Z GFS, is showing
slightly more disagreement than usual for the synoptic scale
pattern, including as early as Monday. The greatest differences
early on exist across the northern Gulf region regarding the
timing of individual shortwave perturbations, and also across the
Arctic Coast region. Differences become substantial across the
eastern Gulf by midweek regarding a potential trough/upper low,
and then across the entire domain by the end of the week. There
is general agreement that a broad upper level low will exist
across the Bering, but limited confidence with low pressure
systems pivoting around the main upper low. Therefore, the
ensemble means accounted for about 2/3 of the model blend by next
Friday to account for the uncertainty, and some previous WPC
continuity for the Monday through Thursday time period.
...Weather/Hazards Highlights...
Additional surface lows into early next week will continue to keep
unsettled conditions across the Aleutians and farther east towards
Southwestern Alaska and the Alaska Peninsula with onshore flow for
these areas, then downstream for southern to Southeast Alaska.
This will be fueled by general moist southerly flow as surface
lows split over the North Pacific into the northern Gulf of
Alaska, with periodic activity with weakened systems working
across the Gulf of Alaska toward the Southeast Panhandle region.
However, most of the precipitation should be light for the
majority of locations affected. There should be an overall
improvement of the frigid pattern over the mainland as upper
ridging builds over the state. By next Monday-Tuesday, the
greatest moderation should be across western Alaska and the North
Slope along with parts of Southwest Alaska, and a strong contrast
to conditions currently.
Hamrick
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