Prognostic Meteorological Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8

000
FXUS10 KWNH 261614
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1214 PM EDT THU MAY 26 2016

VALID MAY 26/1200 UTC THRU MAY 30/0000 UTC

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

12Z NAM/GFS EVALUATION WITH PRELIMINARY MODEL PREFERENCES
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
NAM/GFS INITIALIZATION ERRORS DO NOT SEEM TO DEGRADE THEIR SHORT
RANGE FORECASTS.


SYSTEM PIVOTING THROUGH THE NORTHWEST FRIDAY
CLOSED LOW MOVING INTO THE DESERT SOUTHWEST SUNDAY
SYSTEM MOVING THROUGH SOUTHEAST CANADIAN FRI/SAT
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFER A GENERAL MODEL COMPROMISE HERE TO DEAL WITH ANY LINGERING
DETAIL ISSUES WITH THESE TWO SYSTEMS, AS THE GUIDANCE SHOWS GOOD
AGREEMENT OTHERWISE.


SYSTEM MOVING FROM THE SOUTHWEST THROUGH THE NRN PLAINS
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GFS/ECMWF/CANADIAN COMPROMISE
CONFIDENCE: SLIGHTLY ABOVE AVERAGE

THE 00Z UKMET WAS OVERLY DEEP WITH THIS SYSTEM AS A WHOLE -- ONE
OF ITS USUAL BIASES.  THE 12Z NAM BECAME SLOWER AND SHARPER ALOFT
-- ITS USUAL BIAS THREE DAYS OUT IN TIME.  A COMPROMISE OF THE 12Z
GFS/00Z ECMWF/00Z CANADIAN FIT THE 00Z ENSEMBLE LOW CLUSTERING THE
BEST WITH THE VARIOUS LOWS COMPRISING SYSTEM, SO IT IS PREFERRED
WITH SLIGHTLY ABOVE AVERAGE CONFIDENCE.



UPPER LOW IN THE FL STRAITS
CONVECTIVE LOW APPROACHING SOUTHEAST COAST
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: NON-CANADIAN COMPROMISE
CONFIDENCE: ABOVE AVERAGE

THE 00Z CANADIAN OUTPACED THE REMAINDER OF THE DETERMINISTIC AND
ENSEMBLE ENVELOPE.  A COMPROMISE OF THE 12Z GFS/12Z NAM/00Z
ECMWF/00Z UKMET FITS THE ENSEMBLE CLUSTERING THE BEST AND IS CLOSE
TO THE POINTS COORDINATED WITH THE NATIONAL HURRICANE CENTER AT
16Z, SO IT IS PREFERRED.


...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.