Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
545 PM EDT Sun Jul 05 2020
Valid 12Z Thu Jul 09 2020 - 12Z Mon Jul 13 2020
...Overview and Guidance/Predictability Assessment...
Upper troughing will settle over western Alaska later in the next
week as the flow across the North Pacific flattens. A cold front
will push away from Southcentral and into/through the Gulf toward
Hadai Gwaii. Another system from the central North Pacific will
eventually move toward the eastern Aleutians/AKPEN/Kodiak later
this coming weekend, perhaps as weakening waves. A consensus blend
served well to start the forecast, with the ensembles squarely
between the GFS and ECMWF/Canadian/UKMET. Given the shifts in the
forecast the past few days, all deterministic models were
generally within tolerance. By next Sun/Mon, flattening pattern
across the Pacific favors quicker/weaker (and hard to forecast)
features, depicted as weak waves along a mostly continuous
boundary near and south of the Aleutians. To the north, upper
troughing should hold over western Alaska to the southeast of
upper ridging over the Arctic.
...Weather/Hazard Highlights...
Troughing will promote generally near to cooler than average
temperatures over most of the state next week into the weekend,
perhaps by 10-15 degrees over the Brooks Range. Parts of western
coastal areas as well as the Aleutians may see near to above
average temperatures. Showers will be favored over the Alaska
Range amid daytime heating and cooling mid-level temperatures.
Some areas could see heavier amounts. Showers are possible over
the western Aleutians Thu-Fri as a front dissipates nearby.
Showers will skirt along the Panhandle with the system in the Gulf
late Thu into Fri and perhaps Sat. Only isolated showers are
expected north of the Brooks Range on the Arctic Slope.
Fracasso
Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards 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