Alaska Extended Forecast Discussion
National Weather Service College Park MD
732 PM EDT Thu Apr 30 2026

Valid 12Z Mon 04 May 2026 - 12Z Fri 08 May 2026


...General Overview...

One low pressure system will be weakening as it moves inland over
Alaska this weekend, with another low arriving at the Southern
Coast by around Monday or Tuesday. This system may bring a period
of moderate to heavy precipitation to parts of the Kenai Peninsula
and Southern Coast, with lighter precipitation moving into parts
of the Interior as well. Behind this, the general storm track will
be across the western/central Aleutians and into the Gulf as
ridging builds again over the eastern Interior with weak troughing
over the west coast.


...Guidance Evaluation/Preferences...

There is relatively good agreement on the overall pattern
evolution over Alaska, but considerable uncertainty in the details
and timing of individual systems. As the period starts Monday,
the ECMWF remains notably slower than the remainder of the
guidance with a low lifting north through the Gulf. The consensus
is for something faster, and the 12z ECMWF this afternoon did
trend a bit faster than the 00z run, but still slower than
consensus. After this, models struggle with the timing, location,
and strength of another shortwave through the Aleutians around
Tuesday, which looks to drop well south of the Gulf and weaken.
This happens in favor of another stronger upper low behind it
which may track just south of the Aleutians towards the Gulf late
week. The notable outlier here is the EC-AIFS which is quite a bit
faster, and the GFS is elongated with the overall upper low,
owing to more interaction with the shortwave ahead of it. Seems
the best approach for now is to trend the WPC forecast more
towards a blend of majority ensemble mean guidance to help
mitigate the differences which still need to be resolved.


...Weather/Hazards Highlights...

Light precipitation will be moving into the Interior as the
period begins associated with a weakening low pressure system. The
next low will likely bring moderate to heavy precipitation (snow
in the higher terrain) and a heavy precipitation hazards area was
added today covering Monday-Tuesday. Another round of light
precipitation will accompany this system thereafter as this low
moves inland mid next week. A couple of shortwaves across and
south of the Aleutians will bring unsettled conditions through
most of next week for this region. Temperatures should trend
cooler early next week as ridging over the state weakens/pushes
eastward and troughing moves in. Temperatures may trend above
normal again for parts of the Interior as another round of strong
ridging builds.

Santorelli


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