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FXAK02 KWNH 312249
PMDAK

Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
648 PM EDT Tue Mar 31 2020

Valid 12Z Sat Apr 04 2020 - 12Z Wed Apr 08 2020

...A Stormy Pattern for Alaska...

...Guidance/Predictability Assessment...

The WPC Alaskan medium range product suite was primarily derived
from a composite blend of reasonably well clustered guidance from
the 12 UTC GFS/ECMWF and 12 UTC GEFS/NAEFS/ECMWF ensemble means
along with the 19 UTC National Blend of Models. Forecast spread
has improved through medium range time scales, bolstering forecast
confidence. This forecast strategy has been collaborated with
Alaskan offices and maintains good WPC continuity in an active and
stormy weather pattern.

...Weather/Threats Highlights...

Dynamic mid-upper level trough/jet progression northeastward from
the northern Pacific through the Bering Sea will support a well
developed surface low/frontal system. This storm presents a
maritime threat Saturday with hazardous coastal conditions
including high winds possible into western/northwestern Alaska.
Anomalous stormy weather including heavy snows will translate
inland into the Interior and North Slope over the weekend and in
addition act to cool anticedent much warmer than normal
temperatures. The intrusion of Arctic stream energies may lead to
upper closed low formation by Monday in an unsettled/cooling
pattern for the Interior. Subsequent digging and energy
transference may support well organized low/system formation over
the northern and eastern Gulf of Alaska early-mid next week would
offer a maritime threat along with a weather/precipitation threat
for the southern/southeastern Alaskan tier. Meanwhile well
upstream, there is a growing guidance signal in support for the
gradual approach of amplified mid-upper level closed low/trough
and deepened surface system over the north Pacific toward the
western Aleutians next midweek.

Schichtel

Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php

Hazards:
- High winds across portions of mainland Alaska, Fri-Sat, Apr
3-Apr 4.
- Much above normal temperatures across portions of mainland
Alaska, Fri-Sat, Apr 3-Apr 4.

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

$$




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