Prognostic Meteorological Discussion
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FXUS10 KWNH 160458
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1258 AM EDT TUE SEP 16 2014

VALID SEP 16/0000 UTC THRU SEP 19/1200 UTC

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

00Z NAM/GFS EVALUATION ALONG WITH PREFERENCES/CONFIDENCE
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

THERE DID NOT APPEAR TO BE ANY INITIALIZATION ERRORS WITH THE 00Z
NAM/GFS DEEMED SIGNIFICANT ENOUGH TO IMPACT THEIR FORECASTS.


FULL LATITUDE TROF OVER NORTHEASTERN NORTH AMERICA
STRONG COLD FRONT MOVING THROUGH THE NORTHEAST ON WED
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: BLEND OF THE 00Z GFS/12Z ECMWF
CONFIDENCE: SLIGHTLY ABOVE AVERAGE

AN AMPLIFIED UPPER PATTERN REMAINS IN PLACE ACROSS MUCH OF THE
NORTHEASTERN SECTOR OF THE CONTINENT WITH A BAND OF HEIGHT FALLS
TRAVERSING THROUGH THE UPPER MID-ATLANTIC EARLY TUESDAY MORNING.
ALL MODELS AGREE THIS ENERGY WILL RACE UP TOWARD FAR EASTERN
CANADA WITH ADDITIONAL ENERGY DIGGING UPSTREAM TOWARD
ONTARIO/QUEBEC. AT THE SURFACE...THE 12Z UKMET IS A TAD FASTER
WHILE THE 00Z NAM IS ONE OF THE SLOWER SOLUTIONS NOTED. THE
ENSEMBLE MEANS ARE PRETTY MUCH IN LINE WITH ONE ANOTHER WITH THE
00Z GFS/12Z ECMWF BEING THE MOST REPRESENTATIVE OF SUCH SOLUTIONS.
WPC WILL RECOMMEND A 00Z GFS/12Z ECMWF BLEND.


WEAK SURFACE WAVE MOVING INTO SOUTH TX EARLY TUE
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: A NON-00Z NAM MODEL CONSENSUS
CONFIDENCE: ABOVE AVERAGE

A WEAK AREA OF LOW PRESSURE WILL EVENTUALLY REACH SOUTH TX BY
EARLY TUESDAY. THE 00Z NAM IS PERHAPS A LITTLE FASTER WITH ITS
SOLUTION WITH OTHER MODELS IN FAIRLY GOOD AGREEMENT. WILL
RECOMMEND A NON-00Z NAM MODEL CONSENSUS.


STALLED FRONT/SURFACE WAVES ACROSS THE SOUTHEASTERN U.S.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: A NON-12Z CMC MODEL COMPROMISE
CONFIDENCE: AVERAGE

THE 03Z WPC SURFACE ANALYSIS SHOWED A BOUNDARY STALLED ACROSS THE
DEEP SOUTH AND THROUGH THE SOUTHEASTERN U.S. THIS BOUNDARY WILL
SLOWLY NOSE SOUTHWARD AND REMAIN A FOCUS FOR CONVECTION THE NEXT
COUPLE OF DAYS ALONG THE GULF COAST REGION. MODELS ARE FAIRLY
CLOSE TO ANOTHER WITH THE EXCEPTION OF THE 12Z CMC WHICH KEEPS THE
FRONTAL ZONE A BIT FARTHER SOUTH WHICH ALTERS THE AREA OF HIGHER
QPF. WILL RECOMMEND A NON-12Z CMC MODEL COMPROMISE.


DEEP UPPER TROF AFFECTING THE WESTERN STATES WED-FRI
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: BLEND OF THE 00Z GFS/12Z ECMWF
CONFIDENCE: AVERAGE

THE UPPER RIDGE INITIALLY POSITIONED OVER THE WESTERN U.S. WILL
ADVANCE EASTWARD AHEAD OF A BROAD AREA OF HEIGHT FALLS MOVING
TOWARD THE COAST. THE CORE OF THE LOWEST HEIGHTS WILL CROSS 130W
BY WEDNESDAY MORNING WITH THE 12Z CMC/UKMET WEST OF THE ENSEMBLE
MEANS AT THIS POINT. THE CMC/UKMET FAVORED THIS SLOWER SOLUTION
LAST NIGHT AS WELL. BY THURSDAY...THE SYSTEM SPLITS WITH SOME
ENERGY JOINING THE NORTHERN STREAM WHILE A CORE OF THE VORTICITY
DIGS INTO NORTHERN/CENTRAL CA. THE ENSEMBLE MEANS REMAIN A STEADY
SOLUTION THROUGHOUT THE EVOLUTION WITH THE 00Z GFS/12Z ECMWF
PROVIDING A REASONABLE REPRESENTATION OF THESE MEANS. A 00Z
GFS/12Z ECMWF BLEND WILL BE THE PREFERENCE.


TROPICAL STORM ODILE
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: BLEND OF THE 00Z NAM/GFS...SHIFT EAST OF THEIR BLEND
BEYOND 17/1200Z

RECENTLY DOWNGRADED TO A TROPICAL STORM...ODILE CONTINUES TO DUMP
VERY HEAVY RAINFALL ACROSS BAJA CA WITH ITS MOISTURE EVENTUALLY
LIFTING INTO THE DESERT SOUTHWEST AND FOUR CORNERS REGION. DURING
THE FIRST 12 HOURS OF THE FORECAST...THE 12Z CMC/ECMWF/ECMWF
ENSEMBLE MEAN ARE SLOWER THAN THE NHC TRACK. EVENTUALLY THE SYSTEM
IS EXPECTED TO MAKE A TURN TOWARD THE NORTHEAST CROSSING THE GULF
OF BAJA CA/SEA OF CORTEZ BY EARLY WEDNESDAY. THROUGH 36
HOURS...17/1200Z...THE 00Z NAM/GFS PROVIDE THE BEST GUIDE TO THEIR
TRACK. BY 18/0000Z ONWARD...THE 00Z NAM/GFS ARE WEST OF THE TRACK
WITH THE NAM BEING SLOWER AND THE GFS FASTER. FROM WEDNESDAY
MORNING IT WOULD BE BEST TO BLEND OF THE 00Z NAM/GFS BUT SHIFT THE
AXIS OF FOCUS TOWARD THE EAST.


...MODEL TREND GRAPHICS AT
www.wpc.ncep.noaa.gov/html/model2.shtml...
...500 MB FORECASTS AT
www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml...


RUBIN-OSTER

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