Prognostic Meteorological Discussion
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FXUS10 KWNH 260423
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1223 AM EDT WED APR 26 2017

VALID APR 26/0000 UTC THRU APR 29/1200 UTC

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

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


SYSTEM APPROACHING BRITISH COLUMBIA SATURDAY MORNING
STRONG UPPER LOW DIGGING INTO THE FOUR CORNERS FRI NIGHT
CYCLONE MOVING UP THE EAST COAST THROUGH THURSDAY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
THE GUIDANCE SHOWS GOOD AGREEMENT WITH THESE SYSTEMS.  A
COMPROMISE OF THE AVAILABLE GUIDANCE -- SIMILAR TO THE PARALLEL
VERSION OF THE NATIONAL BLEND OF MODELS -- IS PREFERRED WITH ABOVE
AVERAGE CONFIDENCE.


SYSTEM MOVING NORTHWARD ACROSS THE PLAINS, SOUTHEAST
CANADA, TOWARDS NEW ENGLAND SATURDAY MORNING
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: NON-ECMWF COMPROMISE
CONFIDENCE: ABOVE AVERAGE

THE 12Z ECMWF EVENTUALLY OUTPACES THE REST OF THE GUIDANCE FRIDAY
NIGHT INTO SATURDAY MORNING.  SINCE ITS OWN ENSEMBLE MEAN IS
SLOWER, PREFER A COMPROMISE OF THE 00Z GFS, 00Z NAM, 12Z CANADIAN,
AND 12Z UKMET 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
$$





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