Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
658 PM EST Tue Jan 31 2023
Valid 12Z Sat Feb 4 2023 - 12Z Wed Feb 8 2023
...Pattern overview and Weather/Hazard Highlights...
The main focus in the extended forecast will be the approach of a
strong low from the North Pacific that'll head in the general
direction of the Kenai Peninsula and southern mainland coast late
Sunday and into Monday. There is the potential for widespread
gale to storm force winds over the open waters, and gusty winds
for the coastal areas. There remains a decent signal for heavy
coastal rain and mountain snow from the Kenai Peninsula to the
Chugach Mountains. Strong gap winds are also a possibility
depending on how the low tracks. In terms of temperatures, the
greatest negative anomalies are expected from the Brooks Range to
the Arctic Coast, where readings could be up to 25 degrees below
early February averages.
...Model Guidance/Predictability Assessment...
The models are generally in good agreement across most of the
Alaska domain on Saturday, although the CMC is farther north than
the model consensus with the surface low over the east Gulf
region. Differences become more significant going into Sunday
with the big storm system approaching the southern mainland coast,
with the CMC to the east and the GFS stronger and southwest of the
ECENS/ECMWF guidance. As the low weakens with inland approach
Monday night, the low position is a bit surprisingly more in
agreement here. However, uncertainty becomes high across the
North Pacific going into the beginning of next week with another
storm system tracking in the general vicinity of British Columbia
and another trailing the initial Gulf low. The fronts/pressures
forecast was hedged more in the direction of the GFS/ECMWF for the
first two days owing to the more substantial differences noted
with the CMC. For Monday and beyond, more of the ensemble means
were incorporated into the forecast process.
Hamrick
Hazards:
- Heavy precipitation across the eastern Kenai Peninsula, Sun, Feb
5.
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