576
FXAK02 KWNH 042147
PMDAK

Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
547 PM EDT Tue Jun 04 2024

Valid 12Z Sat Jun 08 2024 - 12Z Wed Jun 12 2024

...Guidance Evaluation and Preferences...
Early on, the 12z guidance shows good agreement. From this weekend
onward, the 12z ECMWF (and to some degree the 00z ECMWF ensemble
mean) bring a cold low from eastern Asia southward into the north
Pacific, which lures a cyclone from east of Japan northeast into
the Aleutians.  This is not seen on other deterministic guidance,
doesn`t fit the idea of broad ridging near the system`s base, and
barely showed up on the 00z ECMWF mean, so used lesser amounts of
the 00z ECMWF from this weekend onward.  An overall deterministic
blend was used early, before switching out the 12z UKMET and 12z
ECMWF for an even amount of the 00z ECMWF/12z NAEFS ensemble means.


...Weather/Hazards Highlights...
To the south, expect a deepening storm system will lift from the
central Pacific to the Gulf of Alaska, while weakening on final
approach, late week into next weekend in conjunction with an
upstream deepened system now tracking by the AK Peninsula into the
northeast Pacific. The combination of these systems should allow
for gales well out at sea, with some enhanced wrapping rains
working into the Aleutians and from Southeast Alaska through the
coastal southern Alaskan tier into the weekend and lingering into
early next week with continued storm rotation offshore, which is
the depicted risk area in the hazards outlook.  Moderate to
occasionally heavy rain then shifts east around the increasingly
barotropic low form south-central AK into the AK Panhandle by
early next week.  Interior shower chances exist due to daytime
heating at the periphery of the nearly cold low.  High
temperatures range from the mid to upper 30s along the North
Slope, to the 40s and 50s along the southern coast, to lower 70s
inland.  Subfreezing low temperatures appear confined to the North
Slope and higher elevations in south-central and southeast AK
between late this week and early next week.

Roth


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

$$