MODEL DIAGNOSTIC DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1123 AM EST THU FEB 13 2014 VALID FEB 13/1200 UTC THRU FEB 17/0000 UTC ...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR INGEST... 12Z NAM/GFS EVALUATION WITH PRELIMINARY MODEL PREFERENCES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT RANGE FORECASTS. SYSTEM MOVING NEAR THE WRN US/CANADIAN BORDER SAT/SUN DEEP CYCLONE APPROACHING SOUTHWEST CANADA SUN ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: AVERAGE THE GUIDANCE IS IN GOOD AGREEMENT WITH THESE TWO SYSTEM, WITH ONLY MINOR PROGRESSION ISSUES AND DEPTH ISSUES ALOFT WITH DETERMINISTIC GUIDANCE (ECWMF AND GFS) MIRRORING THEIR ENSEMBLE MEAN COUNTERPARTS. TO DEAL WITH THE LINGERING UNCERTAINTY, A GENERAL MODEL COMPROMISE IS PREFERRED WITH AVERAGE CONFIDENCE CONSIDERING THEIR PROGRESSIVE NATURE. DEEPER CYCLONE MOVING BY NEW ENGLAND SAT/SUN ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: NON-UKMET COMPROMISE CONFIDENCE: AVERAGE THE 00Z UKMET IS THE SHARPEST AND SLOWEST WITH THIS SYSTEM'S PROGRESSION. THE SYNOPTIC PATTERN SHOWS THE UPSTREAM RIDGE BREAKING DOWN IN THE NORTHERN PLAINS SATURDAY MORNING, WHICH WOULD ARGUE FOR A BROADER/QUICKER MOVING SYSTEM DOWNSTREAM. THE GLOBAL ENSEMBLE CLUSTERING IS CLOSER TO THE 12Z NAM/00Z ECMWF IN TWO DAYS, BEFORE SHIFTING TOWARDS THE QUICKER 12Z GFS/00Z CANADIAN SOLUTIONS THEREAFTER. THE 00Z ECMWF/06Z GEFS/09Z SREF MEANS ALL LIE IN BETWEEN THE SLOWER AND QUICKER CAMPS. THE 12Z GFS MIGHT BE SUFFERING SOME CONVECTIVE/GRIDSCALE FEEDBACK IN ATLANTIC CANADA SATURDAY NIGHT, WHICH HELPING TO LEAD TO ITS GREATER PROGRESSION. DUE TO THE ABOVE, PREFER A GENERAL MODEL COMPROMISE, CLOSE TO THE ENSEMBLE MEANS, WITH AVERAGE CONFIDENCE DUE TO ITS PROGRESSIVE NATURE. CYCLONE MOVING UP THE EAST COAST THU/FRI ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PREFERENCE: GENERAL MODEL COMPROMISE CONFIDENCE: AVERAGE THE GUIDANCE IS IN GOOD AGREEMENT WITH THIS SYSTEM. THE 06Z/12Z GFS DISPLAY WHAT APPEARS TO BE A CONVECTIVE/GRIDSCALE FEEDBACK BULL'S EYE BETWEEN ALBANY NY AND CONCORD NH, WHICH MAY CONTAMINATE ITS PRECIPITATION OUTPUT AND COULD BE OVER-STRENGTHENING ITS 500 AND 700 HPA SLICES OF THIS SYSTEM. TO ACCOUNT FOR POSSIBLE GFS GRIDSCALE CONTAMINATION, THE PREFERENCE IS FOR A GENERAL MODEL COMPROMISE WITH AVERAGE CONFIDENCE CONSIDERING ITS PROGRESSIVE NATURE. www.wpc.ncep.noaa.gov/html/model2.shtml... ROTH