MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 302 PM EDT WED SEP 17 2014 VALID SEP 17/1200 UTC THRU SEP 21/0000 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 12Z MODEL EVALUATION...INCLUDING THE NAM/GFS/UKMET/GEM AND THE ECMWF ...TROPICAL DEPRESSION ODILE... PREFERENCE: THE LATEST NHC TRACK FORECAST T.D. ODILE HAS MADE LANDFALL AS OF THE 18Z NHC INTERMEDIATE ADVISORY OVER NORTHWESTERN MEXICO AND IS EXPECTED TO MOVE FARTHER INLAND WHILE RAPIDLY WEAKENING OVER THE NEXT 24 HOURS. THE SYSTEM SHOULD BEGIN TO SHEAR APART WITH A MID LEVEL CENTER RACING AND SHEARING EAST-NORTHEAST ACROSS THE SOUTHERN ROCKIES AND OUT INTO THE SOUTHERN HIGH PLAINS OVER THE NEXT COUPLE OF DAYS. THE LATEST NHC TRACK FORECAST IS CLOSEST TO A BLEND OF THE 12Z UKMET AND 12Z ECMWF. THE ENERGY ALOFT SHEARING DOWNSTREAM SHOULD TEND TO BE MORE PROGRESSIVE. THE UKMET AND ECMWF THOUGH HAVE SHIFTED THEIR RESPECTIVE TRACKS OF THE VORT ENERGY FARTHER SOUTH...SUGGESTING THAT THE NAM AND GFS ARE TOO FAR NORTH. THERE IS EVIDENCE THAT THE GFS IS SUFFERING FROM CONVECTIVE FEEDBACK PROBS AND AS RESULT PLACING ITS VORT TOO FAR NORTH OVER THE SOUTHERN HIGH PLAINS. THE NAM ASSUMES A MORE NORTHEAST TRACK...BUT EVEN THE LATEST SAT TRENDS SUGGEST A MOTION MORE TO THE EAST-NORTHEAST. SO...BASED ON THIS...A SOLN MORE CLOSELY TIED TO A 12Z UKMET/12Z ECMWF BLEND APPEARS REASONABLE WITH THE ENERGY SHEARING DOWNSTREAM. ...DEEP UPPER TROUGH AFFECTING THE WESTERN STATES THROUGH SAT... PREFERENCE: BLEND OF THE 12Z GFS AND 12Z ECMWF CONFIDENCE: ABOVE AVERAGE THE LARGER SCALE RIDGE POSITIONED OVER THE WESTERN U.S. WILL SHIFT EASTWARD AHEAD OF A BROAD UPPER TROUGH OFFSHORE THE WEST COAST THAT WILL BE DIGGING INTO THE SOUTHWEST U.S. BY FRI. IN GENERAL ALL OF THE MODELS SHOW VERY GOOD MASS FIELD AGREEMENT WITH THE EVOLUTION OF THIS SYS THROUGH SAT. THE OVERALL BEST MODEL CLUSTERING WOULD SUPPORT A BLEND OF THE 12Z GFS AND 12Z ECMWF...AND THAT WILL BE THE PREFERENCE. ...UPPER TROUGH OVER THE NORTHEAST... PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE AN UPPER TROUGH WILL BE SWINGING THROUGH THE NORTHEAST OVER THE NEXT 36 HOURS...AND THE LATEST GLOBAL MODELS SHOW EXCELLENT MASS FIELD AGREEMENT THROUGH THAT TIME PERIOD AS THE ENERGY THEN LIFTS ACROSS EASTERN CANADA. A GENERAL MODEL COMPROMISE WILL BE PREFERRED. ...UPPER TROUGH DIGGING INTO THE NORTHERN PLAINS ON FRI... PREFERENCE: BLEND OF THE 12Z GFS AND 12Z ECMWF CONFIDENCE: AVERAGE ALL OF THE MODELS INDICATE A TROUGH DIGGING INTO THE NORTHERN PLAINS ON FRI ALONG WITH A COLD FRONT. THE 12Z UKMET AND 12Z GEM ARE MUCH MORE PROGRESSIVE AND SHEARED WITH THEIR SHORTWAVE ENERGY DIGGING ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST. THE 12Z GFS/12Z ECMWF AND ESP THE 12Z NAM ARE SLOWER. THE 12Z NAM APPEARS AS IF IT MAY BE A LITTLE TOO AMPLIFIED. WILL PREFER A BLEND OF THE 12Z GFS AND 12Z ECMWF BASED ON STRONGER MODEL CLUSTERING. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ORRISON