Prognostic Meteorological Discussion
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FXUS10 KWNH 091656
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1255 PM EDT WED JUL 09 2014

VALID JUL 09/1200 UTC THRU JUL 13/0000 UTC

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

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


...UPPER TROF ANCHORING NORTHEASTERN NORTH AMERICA...
...SURFACE BOUNDARY EXITING THE NORTHEASTERN U.S...

PREFERENCE: GENERAL MODEL COMPROMISE
FORECAST CONFIDENCE: SLIGHTLY ABOVE AVERAGE

A DEEP AND ANOMALOUS UPPER TROUGH TROF WILL SLOWLY CRAWL EASTWARD
THROUGH THE ERN STATES THE REST OF THE WORK WEEK. A SERIES OF
SHORTWAVE IMPULSES WILL WORK IN CONJUNCTION WITH AN ASSOCIATED
SURFACE FRONT FOR SCATTERED SHOWERS/STORMS FROM THE MID-ATL AND
SOUTHEAST INTO THE SOUTH. THE GUIDANCE IS OVERALL IN DECENT
AGREEMENT WITH THE UPPER TROUGH/500MB HEIGHTS AND SLOW PROGRESSION
OF THE SURFACE FRONT THURS THROUGH SAT... THOUGH SHORT WAVE DETAIL
DIFFS TOUGHER TO DIAGNOSE. WPC WILL RECOMMEND A GENERAL MODEL
BLEND/COMPROMISE OVER THE THREE DAYS.

...BROAD UPPER TROF MOVING ACROSS WESTERN INTO CENTRAL CANADA...
...SHORTWAVE SLIDING FROM THE NORTHERN PLAINS/UPPER MIDWEST TO
EAST...

PREFERENCE: BLEND OF THE GFS/ECMWF FOR MASS FIELDS/ECMWF FOR SHORT
WAVE DETAILS
FORECAST CONFIDENCE: AVERAGE

MODELS DEPICT A DYNAMIC SYSTEM PROGRESSING FROM WRN TO CENTRAL
CANADA ON THURS AND FRI BEFORE SETTLING OVER CENTRAL CENTRAL
CANADA ON SAT AS A LARGE CLOSED UPPER LOW. THE ASSOCIATED SURFACE
COLD FRONT WILL GRADUALLY PRESS SOUTH THROUGH MUCH OF THE UPPER
MIDWEST... REACHING THE GREAT LAKES INTO THE MID MS VALLEY/CENTRAL
PLAINS BY LATE SAT. JUST OUT AHEAD OF THE COLD FRONT AND
SPECIFICALLY THE ASSOCIATED WARM FRONT... A SHORTWAVE ON THE NRN
EXTENSION OF THE MONSOONAL CHANNEL NEAR NWRN NV/ERN OR WILL GET
CAUGHT UP IN THE WESTERLIES. THIS FEATURE WILL TRACK ACROSS MT/WY
THROUGH THE DAKOTAS WED TO THUR EVENING AND THE UPPER MS VALLEY
INTO THE GREAT LAKES/WRN OH VALLEY BY FRI EVENING BEFORE SHEARING
OUT DOWNSTREAM FOR SAT. THIS COULD BE A FAVORABLE ZONE ON THURS
AND FRI FOR MORE CONCENTRATED CONVECTIVE HEAVY RAIN AREAS ALONG
WITH THE TRAILING END OF THE SURFACE COLD FRONTAL ZONE. THE TAIL
END OF THE FRONT WILL STALL ON SAT FROM THE CENTRAL PLAINS/MID MS
VALLEY OR NEAR THE EDGE OF THE 500MB RIDGE CENTER... AS MORE
MONSOONAL DYNAMICS EJECT FROM THE CENTRAL ROCKIES. WPC REALLY
PREFERS THE MASS FIELDS OF THE ECMWF/GFS FOR THE FCST PERIOD BUT
PREFER THE SHORT WAVE DETAILS OF THE ECMWF OVER THE GFS FRI INTO
SAT.

...WEAK TROF OFFSHORE OF THE WEST COAST LATE IN THE PERIOD...

PREFERENCE: BLEND OF GUIDANCE
FORECAST CONFIDENCE: AVERAGE

AN UPPER DISTURBANCE WELL OFFSHORE OF CA WILL BEGIN TO APPROACH
CENTRAL/NRN CA LATE THURS BEFORE GRADUALLY LIFTING UP THE PAC NW
COAST/INTERIOR NW FRI AND SAT. THE GUIDANCE OVERALL APPEARS TO
HAVE A SOLID HANDLING ON THE PROGRESSION AND TRACK OF THIS SHORT
WAVE IMPULSE THROUGHOUT THE FCST PERIOD ALONG WITH THE POTENTIAL
ISOLATED TSTRM/DRY LIGHTNING ACTIVITY FROM NRN CA NORTHWARD INTO
THE INTERIOR NW.


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

MUSHER

$$




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