534
FXAK02 KWNH 212350
PMDAK

Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
749 PM EDT Fri Jun 21 2024

Valid 12Z Tue Jun 25 2024 - 12Z Sat Jun 29 2024

...Overview and Guidance Evaluation/Preferences...

At the synoptic level the over all pattern continues to favor
three main features and are in fair agreement. However, after
several days the model spread still has not improved much thus
maintaining a lower confidence on the details for the later
periods across the Aleutians and western Mainland. The upper
trough/low pressure system north of the state with pinwheel a bit
before it departs east/southeast into western Canada. As it exits
the chances for showers and thunderstorms will reduce from midweek
onward across the northeast part of the state. The Siberian low
will send multiple impulses through the Bering and toward the
Aleutians as it retrogrades, which will help establish mean trough
in the vicinity of the Aleutians. This will support a couple of
systems near the Aleutians to spread rain to the western and
southern part of the state through the middle and later periods.

Persisted with a starting point of the ECWMF, GFS, CMC and UKMET
before dropping the UKMET, reducing inclusion of the CMC while
adding in the ECWMF and GEFS ensemble means.

...Weather/Hazards Highlights...

This active pattern will keep shower activity possible for the
Brooks Range initially and for much of the southern tier of the
state followed by an increase in coverage across eastern portions
of the Aleutians and western Mainland. Showers and thunderstorms
are expected to produce light to moderate amounts across the
Interior and surrounding areas and with the possibility of dry
lightning strikes, during the afternoons and evenings may increase
the risk for fire weather concerns given the dry fuels across the
region. Weak ridging across the Mainland will maintain near normal
or slightly warmer than normal temperatures. Afternoon maximums
are expected to climb into the 70s for many areas across the
Interior, perhaps reaching 80 degrees for the Yukon Flats, and
also just north of the Alaska Range.  Overnight lows here should
also be rather mild with readings bottoming out from the upper 40s
to upper 50s.  The Arctic Coast will likely remain chilly with
onshore flow from the Arctic Ocean, with highs generally from the
upper 30s to upper 40s.

Campbell


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

$$