Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
607 PM EDT Sat Apr 09 2022
Valid 12Z Wed Apr 13 2022 - 12Z Sun Apr 17 2022
...Pattern and Weather/Hazard Highlights...
An amplified upper ridge over the Mainland becomes more blocky
next week as multiple low pressure systems moderately develop on
the periphery, near the Aleutians/Bering and also with some
uncertainty digging from the Arctic Ocean down through the far
eastern Interior/Gulf of Alaska and western Canada. This pattern
should be conducive for warmer and drier conditions for most
locations; which will limit or negate any potential hazardous
conditions statewide. Precipitation should be limited over the
state during this forecast period in this scenario due to the
shielding/blocky upper ridge. Mainly modest activity with energy
digging to the lee of the upper ridge may be more prolonged with
upper troughs/lows over the southern Bering/Aleutians whose
undercutting system energies eventually emerge into the far
western Gulf of Alaska.
...Guidance/Predictability Assessment...
The 12 UTC GFS/ECMWF/UKMET/Canadian solutions seem decently
clustered day 4/Wed, but considering the blocky pattern am
uncomfortable with the GFS/UKMET days 5/6 that weaken the mainland
ridge more quickly than a favored composite of the similar
ECMWF/Canadian. More pronounced embedded system variances into day
7/8 (next weekend) prompted a switch to ensembles at these longer
time frames and prefer the ECMWF ensemble mean that is slower to
weaken the upper ridge than the GEFS/NAEFS. Noted the
ECMWF/Canadian models by day 7/8Â dig ample upper trough energies
westward into the mainland ridge more strongly than the ECMWF
ensemble mean, but was not embraced.
Schichtel
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