Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
755 PM EDT Sat Oct 12 2024

Valid 12Z Wed Oct 16 2024 - 12Z Sun Oct 20 2024

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

The low pressure system over the northern Gulf of Alaska early in
the week is expected to dissipate going into the middle of the
week.  A surface high will be stretched across the central
Aleutians and into the Bering Sea region, and extending inland
across the Interior.  A low pressure system crosses just south of
the Aleutians through Thursday and reaches the southern Gulf by
Friday, but most of the bad weather should remain south of the
coast.  By late in the period next Sunday, another low may start
approaching the western Bering Sea region.

The 12Z model guidance is in good overall agreement across the
Alaska domain for Wednesday, and a general deterministic model
compromise serves as a good starting point in the forecast
process.  Looking ahead to the end of the week, the guidance
agrees well over the mainland, but modest differences with the low
pressure system over the Gulf.  Much greater differences emerge by
next Sunday with the potential storm approaching the western
Bering, and also across the North Pacific with below average
forecast confidence.  The ensemble means were gradually increased
to about 50% by next weekend.

...Weather/Hazards Highlights...

A quieter weather pattern is expected across most of the state
after a busy short term forecast period.  Precipitation should
abate quite a bit across southern Alaska, with some lingering
showers for the southeast panhandle region for the second half of
the week as the surface low steadily decays.  Farther to the north
across the Brooks Range and up to the Arctic Coast, periods of
snow are likely as an arctic shortwave and surface trough passes
through the region, with several inches of accumulation likely. 
Elsewhere, mainly dry conditions can be expected with just a few
isolated rain/snow showers.

Temperatures will be trending colder across most of the state as a
cold front crosses and brings more of an arctic air mass to the
region, with highs likely near or below freezing for most inland
areas by the end of the week, and mid 30s to mid 40s near the
southern coast.  Some valley locations near the Brooks Range could
have overnight lows near zero by Thursday and Friday.

Hamrick


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