746  
FXUS10 KWNH 170449  
PMDHMD  
 
MODEL DIAGNOSTIC DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
1249 AM EDT THU OCT 17 2019  
 
VALID OCT 17/0000 UTC THRU OCT 20/1200 UTC  
 
...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR  
INGEST...  
 
00Z MODEL EVALUATION WITH PREFERENCES AND CONFIDENCE  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
 
GREAT LAKES CLOSED LOW TRANSFERRING TO DEVELOPING NORTHEAST  
COASTAL SURFACE LOW  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
PREFERENCE: GENERAL MODEL BLEND  
CONFIDENCE: ABOVE AVERAGE  
 
VERY GOOD AGREEMENT NOW WITH THE SYNOPTIC EVOLUTION OF THE  
DEEP/ANOMALOUS STORM SYSTEM AFFECTING THE NORTHEAST U.S. TONIGHT.  
SECONDARY LOW ALONG COAST WILL BECOME PARENT LOW AND DEEPEN  
TONIGHT AND THURSDAY MORNING WITH THE SYSTEM BECOMING STACKED  
LATER THURSDAY AND THURSDAY NIGHT. THERE IS EXCELLENT, ABOVE  
AVERAGE AGREEMENT WITH THE LOW POSITION, STRENGTH, AND TRACK  
THROUGH THE NEXT FEW DAYS SUCH THAT A GENERAL MODEL BLEND IS  
ACCEPTABLE AND THE PREFERRED BLEND.  
 
DEVELOPING AREA OF LOW PRESSURE IN THE GULF  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
PREFERENCE: ECMWF/CMC WITH SOME WEIGHTING TOWARD NAM  
CONFIDENCE: BELOW AVERAGE  
 
BROAD AREA OF LOW PRESSURE LOCATED OVER THE BAY OF CAMPECHE  
CONTINUES TO SHOW INCREASED SHOWER AND THUNDERSTORM ACTIVITY PER  
SATELLITE IR IMAGERY IN THE LAST 6-12 HOURS. THIS SYSTEM IS  
EXPECTED TO GRADUALLY MOVE NORTHWARD AND THEN NORTHEASTWARD OVER  
THE NEXT DAY OR SO AS IT INTERACTS WITH A WEAK MID-LEVEL SHORTWAVE  
VORT OVER TEXAS. MODELS HAVE COME INTO SLIGHTLY BETTER AGREEMENT  
WITH THE IDEA THAT THE BROAD AREA OF LOW PRESSURE WILL BEGIN TO  
MOVE NORTHWARD, BUT THERE REMAINS QUITE A BIT OF SPREAD IN THE  
EVENTUAL TRACK AND INTENSITY AS IT APPROACHES THE CENTRAL GULF  
COAST BY THIS WEEKEND. THE 00Z GFS REMAINS A FAST OUTLIER AND  
SHOULD BE LARGELY DISCOUNTED. THE 00Z NAM MATCHES FAIRLY WELL WITH  
THE 12Z ECMWF/CMC WITH SPEED/POSITION OF THE LOW AS IT CROSSES THE  
SOUTHEAST U.S., THOUGH IT IS TOO DEEP COMPARED TO THE REST OF THE  
GUIDANCE. THE 12Z UKMET WAS DISCOUNTED AS IT WAS TOO DEEP/STRONG  
GIVEN AS THE LOW TRACKED OFF THE NORTH CAROLINA COAST, AND THE  
LATEST 0Z UKMET REMAINS FAST AND TOO STRONG (SIMILAR TO GFS). ITS  
SOLUTION REMAINS DISCOUNTED FOR NOW. ALL TOLD, THE ECMWF/CMC TRACK  
REMAINS THE CLOSEST TO THE CONSENSUS APPROACH AND ITS SOLUTIONS  
ARE PREFERRED AT THIS TIME. FORECAST UNCERTAINTY IS HIGH,  
ESPECIALLY BY DAY 2/3.  
 
MODEL TRENDS AT WWW.WPC.NOAA.GOV/HTML/MODEL2.HTML  
500 MB FORECASTS AT WWW.WPC.NOAA.GOV/H5PREF/H5PREF.SHTML  
 
TAYLOR  
 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab HPC Page
Main Text Page