Skip Navigation Links weather.gov 
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
   QPF
   PQPF
   Flood Outlook
   Winter Weather
   Storm Summaries
   Heat Index
   Air Quality
   Tropical Products
   Daily Weather Map
   GIS Products
Current Watches/
Warnings

Satellite and Radar Imagery
   Satellite Images
   National Radar
Product Archive
WPC Verification
   QPF
   Medium Range
   Model Diagnostics
   Event Reviews
International Desks
Development and Training
   Development
WPC Overview
   About the WPC
   Staff
   WPC History
   Accomplishments
   Other Sites
   FAQs
Meteorological Calculators
Contact Us
   About Our Site
 
USA.gov is the U.S. Government's official web portal to all federal, state, and local government web resources and services.
 
Extended Forecast Discussion
 
(Caution: Version displayed is not the latest version. - Issued 0442Z Aug 29, 2014)
 
Version Selection
Versions back from latest:  0   1   2   3   4   5   6   7   8   9   10   
 
Abbreviations and acronyms used in this product
 
Geographic Boundaries -  Map 1: Color  Black/White       Map 2: Color  Black/White


EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1242 AM EDT FRI AUG 29 2014

VALID 12Z MON SEP 01 2014 - 12Z FRI SEP 05 2014

...OVERVIEW AND GUIDANCE PREFERENCES...

IN A CHANGE FROM RECENT MONTHS... RIDGING IS FORECAST TO BUILD
INTO THE EASTERN THIRD OF THE CONUS NEXT WEEK WHILE TROUGHING IS
FAVORED IN THE PAC NW TOWARD THE HIGH PLAINS. FARTHER UPSTREAM...
A DEEP UPPER LOW SHOULD GRAZE NORTHERN ALASKA AND HELP SEND ENERGY
SOUTHEASTWARD THROUGH THE GULF OF ALASKA TOWARD WA/BC. THE
MODELS/ENSEMBLES SHOW THE MOST SENSITIVITY TO THE DETAILS HERE...
WHICH TRANSLATE TO MOSTLY TIMING DIFFERENCES DOWNSTREAM OVER THE
NORTHERN ROCKIES BY THE END OF NEXT WEEK. ENSEMBLE MEANS ARE
LARGELY IN AGREEMENT THOUGH THE 18Z GEFS OUTPACES THE 12Z ECENS
MEAN BY THURS-FRI NEXT WEEK... IN TYPICAL FASHION. USED A BLEND OF
THE RECENT 12Z/18Z ECMWF/GFS DETERMINISTIC AND ENSEMBLE GUIDANCE
MON-TUE/D3-4 BEFORE DROPPING THE GFS AS IT MAY BE TOO EMPHATIC TO
BRING A SFC WAVE INTO THE GREAT LAKES IN LIGHT OF THE ENSEMBLES
AND PREVIOUS ECMWF RUNS. SPLIT THE ECENS-GEFS DIFFERENCES IN THE
PAC NW BY FRI/D7 WHICH ALIGNS NEAR THE 12Z NAEFS MEAN.


...SENSIBLE WEATHER HIGHLIGHTS...

TEMPERATURES SHOULD FALL BELOW AVERAGE IN THE NORTHWEST THROUGH
MONTANA TOWARD THE HIGH PLAINS WITH THE TROUGHING /INITIALLY...
500 MB HEIGHTS ABOUT 2.5 STD DEV BELOW CLIMO/. THE SOUTHERN PLAINS
AND EAST/SOUTHEAST SHOULD SEE NEAR TO ABOVE AVERAGE TEMPERATURES
WITH EXPANDING RIDGING. PRECIPITATION SHOULD LINGER NEAR THE
FRONTAL BOUNDARY IN THE CENTRAL CONUS /NEAR MISSOURI... ET AL./
BEFORE SHIFTING NORTHWARD AS WELL AS WESTWARD INTO MONTANA AS THE
NEXT TROUGH DIGS INTO THE PAC NW.


FRACASSO