Prognostic Meteorological Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12
749
FXUS10 KWNH 270634
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
234 AM EDT TUE JUN 27 2017

VALID JUN 27/0000 UTC THRU JUN 30/1200 UTC

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

00Z MODEL EVALUATION WITH PREFERENCES/CONFIDENCE INTERVALS
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT
RANGE FORECASTS.


DEEP LAYERED CYCLONE MOVING ACROSS WESTERN CANADA INTO
THE NORTHERN PLAINS EARLY FRIDAY
TROUGH LIFTING OUT OF THE EAST
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
THE GUIDANCE SHOWS EXCELLENT AGREEMENT WITH THESE SYSTEMS, SO
PREFER A COMPROMISE OF THE 00Z NAM, 00Z GFS, 00Z ECMWF, 00Z UKMET,
AND 00Z CANADIAN TO DEAL WITH ANY DETAIL ISSUES WITH ABOVE AVERAGE
CONFIDENCE.


CYCLONE MOVING ACROSS THE PLAINS INTO THE GREAT LAKES
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: NON-CANADIAN; CONFIDENCE ABOVE AVERAGE

THE 00Z CANADIAN WAS A STRONG, SLOW OUTLIER WITH THIS SYSTEM`S
MOVEMENT, WHICH WAS EVIDENT IN ITS SURFACE PRESSURES AND 700 HPA
HEIGHT PATTERN, ITS USUAL BIAS.  THE 00Z UKMET MAY HAVE BEEN A
TOUCH STRONG WITH ITS SURFACE AND 700 HPA REFLECTIONS OF THIS
SYSTEM, BUT IT WASN`T TOO DIFFERENT THAN THE NON-CANADIAN
GUIDANCE.  A COMPROMISE OF THE 00Z ECMWF, 00Z UKMET, 00Z GFS, AND
00Z NAM IS PREFERRED WITH ABOVE AVERAGE CONFIDENCE.


LOW- TO MID-LEVEL WEAKNESS ACROSS THE WESTERN GULF OF MEXICO
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: NON-NAM; CONFIDENCE ABOVE AVERAGE

THE MODELS, OUTSIDE THE NAM, ARE IN GENERALLY IN GOOD AGREEMENT.
THE 00Z NAM IS THE STRONGEST, ITS USUAL BIAS.  PREFER A COMPROMISE
OF THE 00Z CANADIAN, 00Z ECMWF, 00Z UKMET, AND 00Z GFS WITH ABOVE
AVERAGE CONFIDENCE.


WWW.WPC.NCEP.NOAA.GOV/HTML/MODEL2.SHTML... /ALL LOWER CASE/
WWW.WPC.NCEP.NOAA.GOV/H5PREF/H5PREF.SHTML... /ALL LOWER CASE/

ROTH
$$





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.