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000
FXUS10 KWNH 191605
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1205 PM EDT WED JUL 19 2017

VALID JUL 19/1200 UTC THRU JUL 23/0000 UTC

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

...THE PARALLEL GFS WAS UPGRADED TO THE OPERATIONAL GFS WITH THE
12Z MODEL CYCLE TODAY...

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


CLOSED LOW ENTERING PAC NW/SW CANADA THURSDAY MOVING
TOWARDS THE GREAT LAKES SATURDAY
LINGERING SHORTWAVE IN THE CAROLINAS DROPPING DOWN AND
RETROGRADING ALONG THE GULF COAST
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
THE GUIDANCE SHOWS GOOD AGREEMENT WITH THESE FEATURES.  A
COMPROMISE OF THE 00Z CANADIAN, 00Z UKMET, 00Z ECMWF, 12Z GFS, AND
12Z NAM IS ADVISED WITH ABOVE AVERAGE CONFIDENCE.


FLAT QUASI-ZONAL FLOW OVER NORTHERN US WITH EMBEDDED
SHORTWAVES AND WEAK FRONTAL ZONE
DISTURBANCE MOVING THROUGH UT THU/CENTRAL PLAINS FRI/
GREAT LAKES BY SAT
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: NON-NAM BLEND
CONFIDENCE: SLIGHTLY ABOVE AVERAGE

AT 700 HPA, THE NAM IS A BIT STRONGER/FASTER WITH A SYSTEM
CROSSING MI SATURDAY MORNING THAN THE OTHER GUIDANCE, SO MUCH SO
THAT IT BECOMES OUT OF PHASE WITH THE OTHER GUIDANCE.  A
COMPROMISE OF THE 00Z CANADIAN, 00Z UKMET, 00Z ECMWF, AND 12Z GFS
SHOULD WORK OUT WELL HERE WITH ABOVE AVERAGE CONFIDENCE.


www.wpc.ncep.noaa.gov/html/model2.shtml
www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml

ROTH
$$





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