Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
551 PM EDT Thu Jun 09 2022
Valid 12Z Mon Jun 13 2022 - 12Z Fri Jun 17 2022
...Overview and Guidance Evaluation/Predictability Assessment...
Overall, the guidance shows pretty good agreement on an upper low
initially near western Alaska lifting slowly to the north as upper
ridging builds in over the Mainland. To the south, a surface
low/frontal system will slide likely well south of the region. The
GFS is farther north than consensus on this low, which would bring
much higher rain chances to parts of the southern Coast/Kodiak
Island. At this time, WPC favored a deterministic model blend
closer to the 12z ECMWF through day 6 keeping the low farther
offshore. By mid to later next week, a deeper low approaches the
Aleutians with some lingering timing differences, though nothing
too egregious considering the late period time frame. Utilizing
more of the ensemble means (still with at least half deterministic
models for added system definition and strength) for the day 7 and
8 period, provided a good starting point. This maintained
reasonable WPC continuity both with yesterdays forecast as well as
the forecast downstream over the CONUS.
...Weather and Hazard Highlights...
As the upper low meanders in the vicinity of western Alaska, and
with moisture available to stream northward from the Gulf, much of
central and southern Alaska can expect showers throughout much of
next week. Some local enhancement is possible across favorable
terrain, with potential for some moderate to locally heavier rains
along the southern Coast/Kodiak Island though highly dependent on
Gulf low positioning (the GFS is much wetter than the rest of the
guidance at this point). A deeper low towards the Aleutians during
the second half of next week offers a maritime threat, with some
increasing rain chances into the western/central Aleutians and
possible gusty winds. Northern Alaska may see a few showers,
though should remain mostly rain free, with eastern Alaska also
drying out the second half of next week. Much of Alaska begins the
week near or below normal, though as the upper low begins to pull
north allowing for upper ridging to build in, much of the state
should begin to moderate by mid to later next week. Parts of
western/interior Alaska should be mild to warm by later next week.
Santorelli
No significant hazards are expected over Alaska during this
forecast period.
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