374  
FXUS10 KWNH 061626  
PMDHMD  
 
MODEL DIAGNOSTIC DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
1225 PM EDT THU AUG 06 2020  
 
VALID AUG 06/1200 UTC THRU AUG 10/0000 UTC  
 
...SEE NOUS42 KWNO (ADMSDM) FOR THE STATUS OF THE UPPER AIR  
INGEST...  
 
12Z NAM/GFS EVALUATION INCLUDING PREFERENCES AND FORECAST  
CONFIDENCE  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
 
OVERALL WEATHER PATTERN ACROSS THE CONTINENTAL U.S.  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
PREFERENCE: GENERAL MODEL BLEND  
CONFIDENCE: SLIGHTLY ABOVE AVERAGE  
 
FOR THE MOST PART, THERE IS GENERALLY GOOD MODEL AGREEMENT ACROSS  
THE CONUS INTO CANADA THROUGH 10/00Z. THERE ARE SOME MODEL  
DIFFERENCES IN THE PLACEMENT AND STRENGTH OF THE CLOSED MID LEVEL  
LOW TRACKING ACROSS SASKATCHEWAN INTO MANITOBA BETWEEN 08/00Z AND  
10/00Z. THOUGH THE DIFFERENCES ARE RELATIVELY MINOR, THEY DO HAVE  
RAMIFICATIONS DOWNSTREAM, AS SHORT WAVE ENERGY EJECTED FROM THE  
BASE OF THE CLOSED MID LEVEL LOW TRACK THROUGH THE FAST MID LEVEL  
FLOW ACROSS THE NORTHERN MID ATLANTIC AND SOUTHERN NEW ENGLAND,  
ESPECIALLY AFTER 09/00Z. THOUGH THERE IS SOME SPREAD IN THE TIMING  
OF THE SHORT WAVES, THAT WOULD BE EXPECTED IN THE FAST MID LEVEL  
FLOW. OVERALL, A GENERAL MODEL BLEND SHOULD SUFFICE, ALLOWING THE  
TIMING DIFFERENCES TO BE MUTED TO SOME DEGREE.  
 
THERE IS ALSO SOME MODEL SPREAD WITH THE DEVELOPMENT OF A SURFACE  
WAVE ON A FRONT EXTENDING FROM THE UPPER MS VALLEY INTO THE  
CENTRAL HIGH PLAINS AFTER 09/00Z. THE SPREAD MAY BE TIED TO THE  
SHORT WAVE TIMING IN THE FAST MID LEVEL FLOW, BUT THE DIFFERENCES  
IN THE SURFACE LOW PLACEMENT APPEAR TO BE TYPICAL FOR A DAY 2/DAY  
3 FORECAST, SO A MODEL BLEND SHOULD WORK HERE AS WELL.  
 
MODEL TRENDS AT WWW.WPC.NCEP.NOAA.GOV/HTML/MODEL2.SHTML  
500 MB FORECASTS AT WWW.WPC.NCEP.NOAA.GOV/H5PREF/H5PREF.SHTML  
 
THIS PRODUCT WILL TERMINATE AUGUST 15, 2020:  
WWW.WEATHER.GOV/MEDIA/NOTIFICATION/PDF2/SCN20-58PMDHMD_TERMINATION.  
PDF  
 
HAYES  
 

 
 
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