Prognostic Meteorological Discussion
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FXUS10 KWNH 250817
PMDHMD

MODEL DIAGNOSTIC DISCUSSION...RETRANSMITTED
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
417 AM EDT TUE APR 25 2017

VALID APR 25/0000 UTC THRU APR 28/1200 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.


SYSTEM MOVING INTO THE WEST WEDNESDAY
LARGE SCALE TROF IN INTERMOUNTAIN WEST THURSDAY
CONSOLIDATING CYCLONE MOVING UP THE EAST COAST
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
THE GUIDANCE SHOWS GOOD AGREEMENT WITH THESE FEATURES.  THE
PREFERENCE IS FOR A GENERAL MODEL COMPROMISE -- SIMILAR TO THE
PARALLEL VERSION OF THE NATIONAL BLEND OF MODELS -- WITH ABOVE
AVERAGE CONFIDENCE.


SYSTEM MOVING NORTHWARD THROUGH THE PLAINS INTO SE CANADA
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: 12Z ECMWF ENSEMBLE MEAN OR 21Z SREF MEAN
CONFIDENCE: SLIGHTLY BELOW AVERAGE

THE 00Z GUIDANCE, OUTSIDE OF THE NAM AND UKMET, HAS DECIDED TO
ACCELERATE THIS SYSTEM FASTER TO THE NORTH -- THE GFS WAS THE
CANARY IN THE COAL MINE.  HOWEVER, THIS ACCELERATION IS RATHER
SUDDEN IN THE GUIDANCE SUITE.  THEIR LATCHING ON TO A NAM SOLUTION
FROM 24/00Z WHICH IT HAS SINCE ABANDONED IS LESS THAN CONVINCING.
FOR NOW, WILL MODESTLY ADJUST THE MODEL PREFERENCE HERE TO THE 12Z
ECMWF ENSEMBLE MEAN OR 21Z SREF MEAN SOLUTION, WHICH IS PREFERRED
WITH SLIGHTLY BELOW 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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