Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
605 PM EDT Fri May 2 2025

Valid 12Z Tue 06 May 2025 - 12Z Sat 10 May 2025

...Strong winds with moderate to heavy rain to impact southern
parts of the state through Tuesday...

...General Overview...

Much of the southern coast will be impacted by strong winds and
moderate/heavy precipitation as a low tracks across the Gulf
Tuesday into Wednesday. Meanwhile, an upper low crossing the 
Bering Sea will send another surface low pressure system toward
the Aleutians and western Gulf by the end of the week renewing
chances for some precipitation along the southern coast and
Southeast. With the Arctic surface high deminishing temperatures
across the Interior and northeast part of the state will begin to
moderate closer to seasonal normal.

...Guidance/Predictability Assessment...

The latest guidance continues to depict a mean trough over the 
Gulf of Alaska, an Arctic high north of the state and a trough/low
traversing the Bering Sea toward the Gulf of Alaska for the 
extended period. Overall, agreement is fair with both the Gulf of
Alaska low and the Bering Sea low. The UKMET was significantly
faster than the cluster for the Bering Sea and was deemed an
outlier for this cycle. Although there is a fair amount of spread
without the UKMET, consensus has the Bering Sea Low approaching
the Aleutians/western Gulf by Thursday which will usher in another
frontal system and round of precipitation to the southern part of
the state.

WPC utilized a multi-model approach for the forecast, beginning
with the 12Z CMC/GFS/ECMWF/UKMET. The ECMWF ensemble, GEFS and
NAEFS means were added to the blend beyond 144-hr to help mute 
the noise within the guidance for the Bering Sea low.

...Weather/Hazards Highlights...

Strong wind and widespread moderate to heavy precipitation will
persist on the southern coastline in association will a robust low
in stationed in the Gulf of Alaska. Winds and precipitation are
expected to decrease significantly by Wednesday. Higher 
elevations inland may have snow during this period. Cloudy
conditions will prevail as a mean trough will remain over the
Gulf. Below average temperatures across portions of the Interior 
will begin to moderate closer to seasonal average by the end of 
the extended period as the Arctic high weakens and the easterly 
winds decrease.

Campbell


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