Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
555 PM EDT Sun Jul 24 2022
Valid 12Z Thu Jul 28 2022 - 12Z Mon Aug 1 2022
...General Overview...
The persistent upper low and deep trough that has been present
across much of Alaska is forecast to lift out and weaken by the
middle of the week as a more typical July pattern tries to become
established during the extended forecast period. The next system
to watch will be a well defined surface low tracking across the
Aleutians for the end of the week, and this should reach the
northern Gulf region by next Sunday in a weakened state. A brief
period of upper level ridging is expected for the southern half of
the state ahead of the trough, but still remaining rather chilly
north of the Brooks Range.
...Guidance/Predictability Assessment...
The 12Z model guidance suite has very good synoptic scale
agreement through the end of the week across the Alaska domain,
with the greatest differences noted across the Arctic Coast region
with respect to the placement of the polar low (UKMET/GFS farther
east than the CMC/ECMWF). By the weekend, the CMC is slower with
the low across the Bering/Aleutians, whereas the GFS becomes more
potent with the low as it emerges over the northern Gulf region.
By next Monday, the ECMWF becomes stronger with another low
approaching the western Aleutians, but reasonably close in
position compared to the ensemble means and the CMC/GFS. The WPC
forecast is primarily based on a deterministic blend through
Friday, and then transitioning to about half ECENS/GEFS and half
CMC/ECMWF/GFS.
...Sensible Weather...
Much of the state is expected to have a gradual warming trend
going into the middle to end of the week, in contrast to the below
average readings in the short range forecast period. The
exception will likely be from the Brooks Range northward where
cold weather will likely persist a bit longer and not feel like
summer. Highs will likely reach the 70s across much of the lower
elevations of the Interior going into the weekend. The southeast
panhandle region will also likely have warmer than average
temperatures owing to the upper level ridge in place across
southwestern Canada.
In the precipitation department, most of the state should be dry
on Thursday ahead of the next storm system, which will increase
rainfall prospects going into Friday and the weekend from the
eastern Aleutians to the Kenai Peninsula. Some lighter showers
should also affect interior portions of mainland Alaska as well.
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