Prognostic Meteorological Discussion
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FXUS10 KWNH 131618
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1117 AM EST SAT FEB 13 2016

VALID FEB 13/1200 UTC THRU FEB 17/0000 UTC

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

GFS/NAM EVALUATION INCLUDING PRELIMINARY PREFERENCES
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
GFS/NAM INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT
RANGE FORECASTS.


SYSTEM MOVING ACROSS THE MIDWEST TUESDAY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GFS/CANADIAN COMPROMISE
CONFIDENCE: SLIGHTLY ABOVE AVERAGE

THE 00Z ECMWF/00Z UKMET ARE OUTLIERS WITH THIS SYSTEM.  THE 00Z
UKMET BECOMES FLAT BECAUSE IT OVERDEVELOPS THE EASTERN SYSTEM, BUT
IT IS UNCLEAR WHY THE 00Z ECMWF ISN`T SHOWING A STRONGER SYSTEM IN
THIS LOCATION.  THERE IS JUST ENOUGH ROOM ALOFT FOR A BRIEF PERIOD
WHERE A 700/500 HPA CYCLONE COULD CLOSE OFF.  THE 00Z GLOBAL
ENSEMBLE SPREAD FAVORS A COMPROMISE OF THE 00Z CANADIAN/12Z GFS,
WHICH IS PREFERRED WITH SLIGHTLY ABOVE AVERAGE CONFIDENCE.


SYSTEM MOVING THROUGH THE EAST TUESDAY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GFS/CANADIAN COMPROMISE
CONFIDENCE: AVERAGE

THE 00Z UKMET WAS QUITE WOUND UP WITH THIS SYSTEM, OVER A DOZEN
HPA DEEPER THAN THE OTHER GUIDANCE WITH THE LOW`S CENTRAL
PRESSURE.  SINCE THE UPPER LEVEL SYSTEM IS ENTERING A REGION OF
CONFLUENT/QUICK FLOW, A LESS AMPLIFIED SOLUTION IS PREFERRED.  A
COMPROMISE OF THE 00Z CANADIAN/12Z GFS ACCOMPLISHES THIS TO SOME
DEGREE AND SPLITS THE DIFFERENCE IN THE 00Z ENSEMBLE LOW
CLUSTERING, SO THEIR SOLUTION IS PREFERRED WITH AVERAGE CONFIDENCE.


SYSTEM SWINGING THROUGH NEW ENGLAND SUNDAY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
THE GUIDANCE IS IN GOOD AGREEMENT HERE, SO PREFER A GENERAL MODEL
COMPROMISE WITH HIGH CONFIDENCE.


...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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