Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
531 PM EDT Mon Jun 13 2022
Valid 12Z Fri Jun 17 2022 - 12Z Tue Jun 21 2022
...Overview and Guidance Evaluation/Predictability Assessment...
The guidance shows reasonable agreement, both amongst the
deterministic and ensemble mean guidance, which also resemble one
another. The guidance generally agrees on the track of the mature
cyclone moving near the upper Aleutians, AK Peninsula, and
northeast Pacific towards Haida Gwaii late this weekend into early
next week. The 12z Canadian weakened ridging at times in interior
AK unlike the remainder of the guidance late this week into this
weekend, which led to minimal inclusion. Used a blend of the 12z
GFS, 12z UKMET, 12z ECMWF heavy blend early on for the pressures,
fronts, winds, and 500 hPa heights -- which should take care of
the above issues -- before shifting slowly in the direction of the
12z ECMWF, 12z GFS, 12z ECMWF ensemble mean, and 00z NAEFS
ensemble means once we get past the end of the UKMET's run. This
solution kept reasonable continuity.
...Weather and Hazard Highlights...
An upper low lifts away from northwest Alaska and reinforces a
front across north and northwest AK which remains quasi-stationary
through the period. Moisture is available to stream northward
from the Gulf towards this system, much of central and southern
Alaska can expect showers throughout much of next week. Some local
enhancement is possible across favored terrain, including the
Brooks Range at times. A deep low moves near the Aleutians/AK
Peninsula late this week and offers a maritime threat, with
gale-force winds with rain amounts of 2-4" expected in the AK
Peninsula and the Aleutians. Overall, southern AK and the Brooks
Range should be wettest this period, with better chances for
clearing skies in northern portions of the state. Interior and
Southern AK should remain mild to warm, with cooler readings in
the usual spots along the coast, the Aleutians, and the North
Slope.
Roth
No significant hazards are expected over Alaska during this
forecast period.
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