Skip Navigation Links 
NOAA logo - Click to go to the NOAA homepage National Weather Service   NWS logo - Click to go to the NWS homepage
The Weather Prediction Center



Follow the Weather Prediction Center on Facebook Follow the Weather Prediction Center on Twitter
NCEP Quarterly Newsletter
WPC Home
Analyses and Forecasts
   National High & Low
   WPC Discussions
   Surface Analysis
   Days ½-2½ CONUS
   Days 3-7 CONUS
   Days 4-8 Alaska
   Flood Outlook
   Winter Weather
   Storm Summaries
   Heat Index
   Tropical Products
   Daily Weather Map
   GIS Products
Current Watches/

Satellite and Radar Imagery
  GOES-East Satellite
  GOES-West Satellite
  National Radar
Product Archive
WPC Verification
   Medium Range
   Model Diagnostics
   Event Reviews
   Winter Weather
International Desks
Development and Training
WPC Overview
   About the WPC
   WPC History
   Other Sites
Meteorological Calculators
Contact Us
   About Our Site is the U.S. Government's official web portal to all federal, state, and local government web resources and services.
Alaska Extended Forecast Discussion
(Caution: Version displayed is not the latest version. - Issued 1847Z Jun 19, 2019)
Version Selection
Versions back from latest:  0   1   2   3   4   5   6   7   8   9   10   
Abbreviations and acronyms used in this product
View Alaska Map

Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
247 PM EDT Wed Jun 19 2019

Valid 12Z Sun Jun 23 2019 - 12Z Thu Jun 27 2019

An upper level low just west of the Panhandle to start the medium
range period (Sunday) will shift south and remain off the
Northwest U.S. coast for the remainder of the period while upper
level ridging builds across Alaska and holds strong through day 6.
There is some indication in the models that troughing may start to
break down the ridge across the northern mainland by day 7, with
the GFS a bit more aggressive on this than the ECMWF or the
ensemble means. Meanwhile, multiple shortwave perturbations will
rotate around a broad upper level low anchored from the Kamchatka
Peninsula of Russia to the far western Aleutian islands. Ensemble
means continue to hint at a developing omega block across the
Alaska region which would indicate this overall pattern being slow
to change through the entire day 4-8 period. This sends a surface
low into the Bering Sea and a cold front across the central
Aleutians early next week with indications of a second system
developing south of the Aleutians late in the period.

Days 4 and 5 show good enough agreement to warrant a majority
deterministic model blend (between the 12z GFS and 00z ECMWF),
with smaller contributions from the ensemble means (GEFS/ECENS).
After this time, increasing weighting of the ensemble means was
used to mitigate the smaller and less predictable timing and
detail differences with individual systems rotating around the
western Aleutians trough. This results in a forecast fairly close
to yesterdays continuity.

In terms of the sensible weather, most places across the Mainland
should be fairly warm and dry, with the best chance for showers
across the elevated terrain of southern Alaska. Increased rain
chances will be possible across parts of the central and western
Aleutians as southerly flow ahead of the broad upper level trough
advects moisture into the region and a series of surface lows move


Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards chart at:

No significant hazards are expected over Alaska during this
forecast period.

WPC medium range Alaskan products including 500mb, surface
fronts/pressures progs and sensible weather grids can also be
found at: