Prognostic Meteorological Discussion
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000
FXUS10 KWNH 261839
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
238 PM EDT THU MAY 26 2016

VALID MAY 26/1200 UTC THRU MAY 30/0000 UTC

...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR
INGEST...

12Z MODEL EVALUATION WITH PREFERENCES/CONFIDENCE INTERVALS
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT
RANGE FORECASTS.


SYSTEM PIVOTING THROUGH THE NORTHWEST FRIDAY
CLOSED LOW MOVING INTO THE DESERT SOUTHWEST SUNDAY
SYSTEM MOVING THROUGH SOUTHEAST CANADA FRI/SAT
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFER A GENERAL MODEL COMPROMISE HERE TO DEAL WITH ANY LINGERING
DETAIL ISSUES WITH THESE THREE SYSTEMS, AS THE GUIDANCE SHOWS GOOD
AGREEMENT OTHERWISE.


SYSTEM MOVING FROM THE SOUTHWEST THROUGH THE NRN PLAINS
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GFS/ECMWF/CANADIAN COMPROMISE
CONFIDENCE: SLIGHTLY ABOVE AVERAGE

THE 00Z/12Z UKMET WERE OVERLY DEEP WITH THIS SYSTEM AS A WHOLE --
ONE OF ITS USUAL BIASES.  THE 12Z NAM BECAME SLOWER AND SHARPER
ALOFT -- ITS USUAL BIAS THREE DAYS OUT IN TIME.  A COMPROMISE OF
THE 12Z GFS/12Z ECMWF/12Z CANADIAN FIT THE 00Z ENSEMBLE LOW
CLUSTERING THE BEST WITH THE VARIOUS LOWS COMPRISING SYSTEM, SO IT
IS PREFERRED WITH SLIGHTLY ABOVE AVERAGE CONFIDENCE.



UPPER LOW IN THE FL STRAITS
CONVECTIVE LOW APPROACHING SOUTHEAST COAST
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: NON-CANADIAN COMPROMISE
CONFIDENCE: ABOVE AVERAGE

THE 12Z CANADIAN WAS NORTH OF THE REMAINDER OF THE DETERMINISTIC
AND ON THE NORTHERN FRINGE OF THE 00Z GLOBAL ENSEMBLE ENVELOPE.  A
COMPROMISE OF THE 12Z GFS/12Z NAM/12Z ECMWF/12Z UKMET FITS THE
ENSEMBLE CLUSTERING THE BEST AND IS CLOSE TO THE POINTS
COORDINATED WITH THE NATIONAL HURRICANE CENTER AT 16Z, SO IT IS
PREFERRED.


...MODEL TREND GRAPHICS AT
www.wpc.ncep.noaa.gov/html/model2.shtml...

...500 MB FORECASTS AT
www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml...

ROTH
$$




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