Prognostic Meteorological Discussion
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7
000
FXUS10 KWNH 110424
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1223 AM EDT FRI JUL 11 2014

VALID JUL 11/0000 UTC THRU JUL 14/1200 UTC

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


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


DEEP CYCLONE ACROSS SOUTHEAST CANADA
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: CANADIAN/ECMWF/GFS COMPROMISE
CONFIDENCE: ABOVE AVERAGE

AS RIDGING AMPLIFIES OVER THE SOUTHERN CANADIAN ROCKIES, A
DOWNSTREAM COLD LOW IS EXPECTED TO DROP SOUTHWARD TOWARDS
INTERNATIONAL FALLS, WITH A PIECE OF ENERGY ESCAPING NORTHEAST
INTO QUEBEC.  THE 00Z NAM IS THE FARTHEST WEST WITH THIS SYSTEM
AND STRONGER WITH A LOW MOVING THROUGH MICHIGAN -- TWO OF ITS
USUAL BIASES -- WHILE THE 12Z UKMET IS THE QUICKEST -- ONE OF ITS
USUAL BIASES.  CONSIDERING ABOVE, PREFER A COMPROMISE OF THE 12Z
CANADIAN/12Z ECMWF/00Z GFS GUIDANCE WITH ABOVE AVERAGE CONFIDENCE
CONSIDERING THE MODEL BIASES.


SYSTEM MOVING INTO THE NORTHWEST SUNDAY/MONDAY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: NON-CANADIAN COMPROMISE
CONFIDENCE: ABOVE AVERAGE

THE 12Z CANADIAN WAS SLOW WITH THIS SYSTEM -- ITS USUAL BIAS --
WHICH IS EMBEDDED WITHIN MODEST SOUTH-SOUTHWESTERLY FLOW.  THE
PREFERENCE IS FOR A NON-CANADIAN COMPROMISE WITH ABOVE AVERAGE
CONFIDENCE CONSIDERING ITS KNOWN BIAS.


UPPER LEVEL SHORTWAVE MOVING THROUGH NORTHERN MEXICO
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: BLEND OF THE OPERATIONAL MODELS
CONFIDENCE: ABOVE AVERAGE

THE GUIDANCE IS IN GOOD AGREEMENT WITH THIS SYSTEM.  A GENERAL
MODEL COMPROMISE IS PREFERRED WITH ABOVE AVERAGE CONFIDENCE
CONSIDERING THE MINIMAL MODEL SPREAD.


...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
$$





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