Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
501 PM EST Wed Feb 21 2024
Valid 12Z Sun Feb 25 2024 - 12Z Thu Feb 29 2024
...Unsettled pattern for southern Alaska, with cooling conditions
across Mainland Alaska...
...Guidance Evaluation and Preferences...
The 12 UTC GFS/ECMWF/UKMET/Canadian model solutions showed
reasonable agreement into early next week within a
buckling/amplifying flow pattern around the North Pacific as a
whole, though detail issues are larger than seen yesterday. A
favored composite offers maximum system detail consistent with a
pattern with seemingly above normal predictability and reasonable
run to run consistency. WPC product continuity is reasonably well
maintained.
...Pattern Overview and Weather/Hazards Highlights...
A couple of cyclones move through the Gulf of Alaska and the
northeast Pacific this period, with the second system expected to
be stronger than the first. The southern tier of the state,
including the Aleutians, will be wetter/snowier. Both systems
should bring gale to storm force winds across the AK Peninsula,
particularly in areas of gap flow/areas that usually deal with
accelerated winds in northwesterly low-level flow. With high
pressure building into northwest Canada and Alaska, colder
conditions are expected to spread south and southwest across the
Interior into southern AK and the AK Panhandle, with increasingly
large areas of real estate dropping below 0F, if not -20F, for
overnight lows with time. Normally colder eastern interior
locations could flirt with -40F readings for overnight lows. The
trends today were to delay the cooling for southwest AK and trend
somewhat northerly with the second, stronger cyclone with an
associated northerly shift in chances of precipitation and QPF.
For wetter southern areas, rain should slowly transition to snow
as the colder air filters in.
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