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 1914Z Mar 13, 2018)
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
314 PM EDT Tue Mar 13 2018

Valid 12Z Sat Mar 17 2018 - 12Z Wed Mar 21 2018

...Guidance/Uncertainty Assessment and Weather

Medium range model and ensemble forecast spread and implied
uncertainty has decreased a bit today, bolstering confidence a bit
for at least mid-larger scale features. The latest several ECMWF
runs and recent GEFS/ECMWF ensemble means in particular seem
compatable/well clustered through the weekend and even to a lesser
degree through early next week. Accordingly...prefer a blended
forecast solution using these guidance pieces whose resultant
output maintains decent WPC continuity.

In this scenario, arctic mid-upper level trough progression and
associated height falls will accompany frontal passage and modest
snow potential from the North Slope down into the interior this
weekend. Underneath...lead energy splitting eastward meanwhile
leads to a modest surface low/frontal system in the northern Gulf
of Alaska this weekend to support some southern and southeastern
Alaska precipitation.

The active pattern reloads further upstream where there is a
strong guidance signal for deep low development potentials over
the Bering Sea this weekend into early next week. Downstream
propagation of energy may lead to some enhanced flow into western
Alaska and the interior/North Slope as per low and frontal system
approach. Undercutting triple point low development and height
falls also splits underneath to the Gulf of Alaska early next week
to renew potential for another period of modest to locally terrain
enhanced southern and southeastern Alaska precipitation.

Yet another deep low could be brewing upstream over the western
Bering Sea heading into the middle of next week that could act to
overall amplify the flow downstream.