MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1231 AM EDT SUN NOV 06 2016 VALID NOV 06/0000 UTC THRU NOV 09/1200 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 00Z MODEL EVALUATION...INCLUDING THE NAM AND GFS ...UPPER TROUGH CROSSING THE NORTHWEST EARLY SUN... ...CROSSING THE NORTHERN TIER STATES MON... ...AMPLIFYING OVER THE GREAT LAKES/NORTHEAST TUES/WED... PREFERENCE: BLEND OF THE 00Z NAM/00Z GFS/12Z ECMWF CONFIDENCE: AVERAGE THE MODELS TAKE A PROGRESSIVE SHORTWAVE INLAND ACROSS THE PACIFIC NORTHWEST ON SUN WHICH WILL QUICKLY ADVANCE DOWNSTREAM ACROSS THE NORTHERN TIER OF THE NATION BEFORE AMPLIFYING SOUTHEASTWARD BY TUES AND WED ACROSS THE GREAT LAKES AND NORTHEAST. GOOD AGREEMENT IS SEEN IN THE GUIDANCE WITH THIS SYSTEM UNTIL ABOUT EARLY MON WHEN THE 12Z UKMET BEGINS SUPPORTING A MORE AMPLIFIED TROUGH. THIS LEADS TO THE UKMET HAVING A SLOWER/STRONGER TROUGH AND POSSIBLE CLOSED LOW IMPACTING THE GREAT LAKES AND OH VALLEY BY TUES AND WED. THE 00Z NAM/00Z GFS AND 12Z ECMWF ARE ALL A BIT MORE PROGRESSIVE AND LESS AMPLIFIED AND SUGGEST MORE TROUGHING IMPACTING THE NORTHEAST AND MID-ATLANTIC BY WED. THE 12Z CMC GENERALLY AGREES WITH THE TIMING OF THIS CAMP...BUT IS A BIT SHARPER WITH ITS TROUGH OVER THE NORTHEAST BY WED. THE LATEST GEFS MEAN AND ECENS MEAN FAVOR THE NAM/GFS/ECMWF CLUSTER...AND SO WILL FAVOR A CONSENSUS OF THESE SOLUTIONS. ...SHORTWAVE TROUGH/FRONT NEARING THE PACIFIC NORTHWEST BY WED... PREFERENCE: BLEND OF THE 00Z NAM/00Z GFS CONFIDENCE: AVERAGE THERE WILL BE PLENTY OF DEEP TROUGHING OFFSHORE THE WEST COAST FOR MOST OF THE PERIOD...AND THE GUIDANCE HAS A FAIRLY WELL-DEFINED SHORTWAVE EMBEDDED WITHIN DEEPER LAYER SOUTHWEST FLOW THAT WILL BE APPROACHING THE PACIFIC NORTHWEST AND VANCOUVER ISLAND BY WED. THE 12Z UKMET IS THE SLOWEST AND MOST AMPLIFIED WITH THIS FEATURE. THE 00Z GFS HAS TRENDED JUST A TAD SLOWER/DEEPER VERSUS ITS PREVIOUS RUN...BUT IS NOT AS SLOW/DEEP AS THE UKMET. THE 00Z NAM ALSO TRENDED A TAD SLOWER/DEEPER AND IS JUST A LITTLE MORE PROGRESSIVE THAN THE GFS. THE 12Z CMC AND 12Z ECMWF ARE THE MOST PROGRESSIVE AND WEAKEST. BASED ON THE NAM/GFS TRENDS AND THE SPLIT BETWEEN THE UKMET AND THE CMC/ECMWF CAMPS...A COMPROMISE BETWEEN THE NAM AND GFS WILL BE PREFERRED. ...CLOSED LOW/TROUGH WEAKENING OVER THE PLAINS THRU SUN... PREFERENCE: NON-CMC CONSENSUS CONFIDENCE: SLIGHTLY ABOVE AVERAGE THE MODELS ARE IN GOOD AGREEMENT WITH THIS SYSTEM...BUT THE 12Z CMC WAS A TAD QUICKER TO WEAKEN THE SYSTEM VERSUS THE REMAINING GUIDANCE. WILL SUGGEST A NON-CMC CONSENSUS. ...BROAD CLOSED LOW OVER THE SOUTHERN PLAINS THRU TUES... ...ENERGY DIGGING SOUTH INTO NORTHERN MEXICO BY WED... PREFERENCE: NON-NAM CONSENSUS CONFIDENCE: SLIGHTLY ABOVE AVERAGE THE MODELS DEVELOP A BROAD AND ELONGATED UPPER TROUGH AND EMBEDDED CLOSED LOW OVER THE SOUTHERN PLAINS BY TUES WHICH SETTLES SOUTH INTO NORTHERN MEXICO ON WED IN RESPONSE TO A STRENGTHENING RIDGE OVER THE INTERMOUNTAIN WEST. THE 00Z NAM DOES NOT DIG QUITE AS MUCH ENERGY AS FAR SOUTH OR SOUTHWEST AS THE GLOBAL MODELS DO BY WED...BUT THERE IS A GENERAL CONSENSUS OF THE GUIDANCE THAT THERE WILL BE A BROAD CLOSED LOW OVER NORTHERN MEXICO BY EARLY WED. WILL SUGGEST A NON-NAM CONSENSUS BASED ON THE GLOBAL MODEL AGREEMENT/CLUSTERING. ...UPPER TROUGH AMPLIFYING ACROSS NEW ENGLAND THRU SUN... ...CLOSED LOW DEVELOPMENT OFFSHORE BY MON... PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: ABOVE AVERAGE THE MODELS ARE IN GOOD AGREEMENT WITH THIS SYSTEM THROUGH SUN AS IT CROSSES THE NORTHEAST AND THEN AMPLIFIES INTO A CLOSED LOW OFFSHORE BY MON. WILL PREFER A GENERAL MODEL COMPROMISE. ...MID LEVEL TROUGH OVER THE CENTRAL GULF COAST TUES/WED... ...WEAK INVERTED TROUGH/SURFACE WAVE OVER THE NORTHERN GULF OF MEXICO... PREFERENCE: BLEND OF THE 00Z GFS/12Z ECMWF CONFIDENCE: BELOW AVERAGE THE MODELS SHOW A LOW TO MID LEVEL WEAKNESS ELONGATED OVER THE NORTHERN GULF OF MEXICO AND THE CENTRAL GULF COAST REGION BY TUES AND WED...AND THERE IS EVIDENCE OF A WEAK INVERTED SURFACE TROUGH AND SURFACE WAVE OFFSHORE THE CENTRAL GULF COAST. THE 12Z ECMWF IS THE WEAKEST WITH THIS SYSTEM WITH THE 00Z GFS THE STRONGEST. THE GFS HAS SUPPORT FROM THE GEFS MEAN WITH THIS FEATURE AND ALSO TO AN EXTENT THE 00Z NAM AND 12Z CMC. CONFIDENCE IS LOW...BUT COMPROMISING IN BETWEEN THE WEAK ECMWF AND STRONGER GFS WILL BE THE PREFERENCE FOR NOW. www.wpc.ncep.noaa.gov/html/model2.shtml... www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml... ORRISON