Prognostic Meteorological Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8
000
FXUS10 KWNH 020438
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1237 AM EDT THU JUL 02 2015

VALID JUL 02/0000 UTC THRU JUL 05/1200 UTC

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

00Z MODEL EVALUATION...INCLUDING THE NAM AND GFS


...UPPER TROUGH MOVING THROUGH WESTERN CANADA THROUGH SAT/SUN...
...COLD FRONT DROPPING INTO HIGH PLAINS...

PREFERENCE: 12Z ECMWF
CONFIDENCE: AVERAGE

ALL OF THE MODELS SHOW AN UPPER TROUGH DIGGING ACROSS WESTERN
CANADA THIS WEEKEND...WITH THE SOUTHERN PORTION OF THIS DIGGING
ACROSS THE NORTHERN ROCKIES AND HIGH PLAINS. THIS SHOULD DRIVE A
COLD FRONT ACROSS THESE AREAS AS WELL. THE 12Z CMC IS TAD SLOW
WITH THE SOUTHERN PORTION OF THE TROUGH...WITH THE 12Z UKMET
APPEARING TO BE A BIT TOO SHARP WITH AN IMPULSE NEAR THE BASE OF
THE TROUGH. THE 12Z ECMWF/00Z NAM AND 00Z GFS HAVE BETTER
AGREEMENT/CLUSTERING ALOFT. HOWEVER...AT THE SURFACE...THE 00Z GFS
BECOMES THE MOST PROGRESSIVE AS IT RELATES TO THE FRONT. THE 12Z
UKMET BECOMES THE SLOWEST. THE 12Z ECMWF GENERALLY REPRESENTS THE
GLOBAL MODEL CONSENSUS SURFACE AND ALOFT...AND THIS SOLUTION WILL
BE PREFERRED AT THIS TIME.


...SURFACE WAVE MOVING EAST FROM KS TO THE MID-ATLANTIC THROUGH
SAT...

PREFERENCE: BLEND OF THE 00Z GFS AND 12Z ECMWF
CONFIDENCE: AVERAGE

A MID LEVEL SHORTWAVE TROUGH CURRENTLY DIGGING INTO THE MID MS
VALLEY IS EXPECTED TO REACH THE LOWER OH VALLEY THURS NIGHT AND
THE CENTRAL APPALACHIANS FRI NIGHT. THE GUIDANCE OVERALL APPEARS
TO BE IN BETTER MASS FIELD AGREEMENT COMPARED TO PREVIOUS
RUNS...BUT THE 12Z CMC APPEARED TO LOCALLY BE TOO STRONG WITH THE
WAVE. THE 12Z UKMET APPEARED TO BE PERHAPS A TAD TOO WEAK ALOFT
WITH THE ENERGY. THE STRONGER MODEL CLUSTERING GENERALLY FAVORS
THE 00Z GFS AND 12Z ECMWF...AND SO A BLEND OF THESE SOLUTIONS WILL
BE PREFERRED.


...SHORTWAVE CLIPPING THE NORTHERN GREAT LAKES FRI/SAT...

PREFERENCE: BLEND OF THE 00Z GFS AND 12Z ECMWF
CONFIDENCE: AVERAGE

THE 00Z NAM AND 12Z CMC GRADUALLY BECOME THE SLOWEST/STRONGEST
SOLUTIONS WITH THIS FEATURE. THE 12Z UKMET BECOMES THE FASTEST AND
WEAKEST. THE STRONGER CLUSTERING FAVORS THE 00Z GFS AND 12Z
ECMWF...AND A BLEND OF THESE SOLUTIONS WILL BE 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...

ORRISON

$$





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