Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
741 PM EDT Sun Mar 23 2025

Valid 12Z Thu 27 Mar 2025 - 12Z Mon 31 Mar 2025

...General Overview...

A broad upper low/trough is expected to encompass most of the Gulf
region to close out the month of March, with embedded surface lows
rotating around the main vortex. Most of the rainfall associated 
with this should be offshore, although some precipitation may 
reach the southern mainland coast by late Saturday. Meanwhile, a 
strong upper ridge becomes established over the central/western 
Aleutians and over the southern Bering Sea going into the end of 
the week and next weekend, with a warm front lifting northeast 
across western Alaska late in the forecast period bringing light
snow ahead of it.


...Guidance/Predictability Assessment...

The 12Z model guidance suite features good overall agreement
across Alaska on Thursday, and therefore a general deterministic
model blend serves as a good starting point in the forecast
process. This also holds true going into Friday, although
differences become greater with low pressure over the eastern
Gulf. More noteworthy differences become apparent by Sunday and
Monday, with the 12Z GFS more amplified and farther west with the
upper ridge axis over the western Bering, whereas the ensemble
means and CMC/ECMWF favor the ridge axis closer to the western
Alaska Coast. The GFS is also stronger with a surface low over the
central Gulf, so less of the GFS was used by this time. Given the
deterministic spread by next weekend and Monday, the ensemble 
means accounted for about 50-60% of the model blend by that time.


...Weather/Hazards Highlights...

The majority of the state should enjoy a tranquil and dry weather
pattern for the end of the work week, with just a few showers and
mountain snow showers for the southeast Panhandle region. Surface
low re-development over the northern Gulf by the weekend may 
result in additional rain and mountain snow from the Kenai
Peninsula to the Panhandle, but nothing appears to reach 
hazardous level criteria through the entire forecast period and no
atmospheric river events are anticipated. Elsewhere across the
state, warm air advection along and ahead of a warm front
approaching from the Bering Sea will likely produce periods of
light snow across portions of the western mainland late Sunday
into Monday, and perhaps warm enough for some rain closer to the
western coastal areas.

Most of the western and northern mainland should be slightly below
average for Thursday/Friday, followed by a warm-up to generally
above average temperatures by next Monday with southwest flow
ahead of the Bering Sea storm system. Portions of the eastern
Interior will be slowest to erode the colder surface temperatures
as the warm front crosses the state.

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