Prognostic Meteorological Discussion
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000
FXUS10 KWNH 130641
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
240 AM EDT SUN JUL 13 2014

VALID JUL 13/0000 UTC THRU JUL 16/1200 UTC

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


00Z MODEL EVALUATION WITH PREFERENCES
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
NAM/GFS INITIALIZATION ERRORS DO NOT APPEAR TO DEGRADE THEIR SHORT
RANGE FORECASTS.


DEEP/COLD LOW DROPPING INTO MI MON/TUE
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: BLEND OF 00Z GFS/00Z ECMWF
CONFIDENCE: AVERAGE

THE 00Z NAM IS ON THE FASTER EDGE OF THE MODEL SOLUTION ENVELOPE
WITH ITS DEPICTION OF THE CLOSED MID- LEVEL LOW AND ITS LONGWAVE
TROUGH POSITION. THE 00Z GFS HAS CONTINUED TO SLOW ITS PROGRESSION
WITH RESPECT TO THE ANOMALOUS MID-LEVEL CYCLONE OVER ITS PAST DAY
OF RUNS. THE 00Z ECMWF IS STILL ON THE SOUTHWEST SIDE OF THE
GUIDANCE THROUGH DAY 2.  AFTER THAT...THE ECMWF SOLUTION SPEEDS UP
AND CONVERGES TO THE CONSENSUS POSITION. DESPITE THE DIFFERENCES
IN THE TIMING OF THE EXIT OF THE CLOSED MID LEVEL SYSTEM AND
EVOLUTION OF THE LONG WAVE TROUGH...THERE WAS GENERALLY GOOD MODEL
AGREEMENT CONCERNING THE TIMING OF THE FRONT ON THE EAST COAST.
PREFER A COMPROMISE OF THE 00Z GFS AND 00Z ECMWF TO DEAL WITH
DETAIL ISSUES ALOFT, WITH AVERAGE CONFIDENCE CONSIDERING THE
EXISTING MODEL SPREAD.


SHORTWAVES AFFECTING THE NORTHWEST/NORTHERN ROCKIES
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: 00Z UKMET/00Z ECMWF COMPROMISE
CONFIDENCE: ABOVE AVERAGE

THE FIRST SHORT WAVE ORIGINATING ALONG THE WEST COAST CROSSES THE
PACIFIC NORTHWEST AND NORTHERN ROCKIES DURING DAY 2...AND THERE
WAS A GOOD MODEL CONSENSUS WITH THE TRACK AND TIMING OF THIS SHORT
WAVE. A SECOND SHORT WAVE DROPPING OUT OF WEST CENTRAL CANADA
CROSSES THE NORTHERN ROCKIES ON DAY 3. A COMPROMISE OF THE 00Z
UKMET/00Z ECMWF SPLITS THE DIFFERENCE IN TIMING AND KEEPS THE
SYSTEM FROM BECOMING TOO SHARP ALOFT, WHICH IS PREFERRED WITH
ABOVE AVERAGE CONFIDENCE CONSIDERING THE MINIMAL GUIDANCE SPREAD.


INVERTED UPPER TROUGH SKIRTING THE SOUTHWEST THROUGH MON
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GENERAL MODEL BLEND
CONFIDENCE: ABOVE AVERAGE

THE GUIDANCE IS CLUSTERED WELL WITH RESPECT TO THE INVERTED UPPER
TROUGH CROSSING THE SOUTHWEST STATES INTO CA...INCLUDING THEIR
DEPICTION OF THE MOISTURE PLUME ASSOCIATED WITH IT.


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

HAYES/ROTH
$$




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