Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
509 PM EDT Sun Jun 23 2024

Valid 12Z Thu Jun 27 2024 - 12Z Mon Jul 01 2024

...Overview and Guidance Evaluation/Preferences...
The flow around AK morphs back and forth between a Rex and Omega
Block as deep layer lows occasionally move under its southern
side.  Ridging persists across much of mainland AK.  The 12z UKMET
became a northward outlier with the system initially in the Bering
Sea, so used only a small percentage of its solution.  The 12z
runs of the ECMWF, Canadian, and GFS fit in reasonably well with
the 12z NAEFS and 00z ECMWF ensemble means.  For the winds,
pressures, 500 hPa heights, and QPF persisted with a starting
point of primarily the 12z runs of the ECWMF, GFS, and Canadian
models before adding in the ECWMF and GEFS ensemble means.  The
remainder of the grids were more heavily based on the 19z NBM,
with some inclusion of the 12z ECMWF and 12z ECMWF ensemble mean.


...Weather/Hazards Highlights...
This pattern will favor the Aleutians and AK Peninsula to be
rainy, as the Bering Sea cyclone lifts north and a new cyclone and
a new occluded cyclone is escorted under its base late in the
week.  Due to the depth of the low expected in the Bering Sea
early on, up to 40 kt (45 mph) winds are expected to brush up
against westernmost AK next Wednesday and Thursday as the cyclone
weakens.  The pair of systems allow for modest rainfall in their
vicinity.  Thereafter, winds should generally peak in the 30 kt
(35 mph) range across the Arctic Coast and coastal areas.  The
terrain in south-central and northern AK are expected to have the
best chance of showers and thunderstorms. There is the possibility
of dry lightning strikes during the afternoons and evenings which
would increase the risk for fire weather concerns given the dry
fuels across the region.  Ridging across the Mainland will
maintain warm to hot temperatures.  Afternoon maximums should lie
the 80-90F range for the most part across the Interior.  Highs
mostly in the 60s and 70s are expected across lower elevations of
south-central AK, with mainly 50s and 60s in most coastal areas,
50s and 40s across the North Slope, and mid to upper 40s in the
Aleutians.  The North Slope will be cool overnight with lows in
the 30s, while higher elevations in the terrain across
south-central and southeast AK should fall below freezing
overnight. 

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