711
FXUS10 KWNH 111713
PMDHMD
MODEL DIAGNOSTIC DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
112 PM EDT MON AUG 11 2008
VALID AUG 11/1200 UTC THRU AUG 15/0000 UTC
MODEL INITIALIZATION...
..SEE NOUS42 KWNO ADMNFD FOR STATUS OF UPPER AIR INGEST
ANY INITIALIZATION ERRORS WITH THE NAM AND GFS DO NOT APPEAR TO
SIGNIFICANTLY IMPACT THEIR FORECASTS.
MODEL TRENDS...
..UPPER TROUGH OVER THE SAINT LAWRENCE VALLEY
THE NAM SHOWS REASONABLE CONTINUITY WITH THIS SYSTEM. THE GFS HAS
TRENDED WEAKER AND MORE SHEARED WITH THE SHORTWAVE DROPPING INTO
SOUTHEASTERN ONTARIO ON THE BACKSIDE OF THE TROUGH.
..SHORTWAVE ENERGY CROSSING THE OZARKS DAY 1
THE NAM SHOWS REASONABLE CONTINUITY WITH THIS IMPULSE. THE GFS
HAS TRENDED MORE FOCUSED WITH THIS ENERGY OVER NORTHERN
MISSISSIPPI AND ALABAMA BY THE BEGINNING OF DAY 2.
..SHORTWAVE CROSSING THE DAKOTAS AND MINNESOTA DAY 1
THE NAM AND GFS HAVE TRENDED WEAKER AND LESS AMPLIFIED WITH THIS
IMPULSE AS IT DIVES ACROSS THE UPPER MISSISSIPPI VALLEY DAY 2.
..VORTEX OVER SOUTHWESTERN CANADA
THE NAM AND GFS HAS TRENDED SOUTHWARD WITH THIS SYSTEM.
..SOUTHWEST MONSOON
THE NAM SHOWS REASONABLE CONTINUITY OVER THIS REGION. THE GFS HAS
TRENDED MORE INTENSE WITH THE IMPULSE CROSSING THE FOUR CORNERS
EARLY DAY 3.
...MODEL TREND GRAPHICS AT
WWW.HPC.NCEP.NOAA.GOV/HTML/MODEL2.SHTML...
MODEL DIFFERENCES AND PREFERENCES...
..UPPER TROUGH OVER THE SAINT LAWRENCE VALLEY
THE NAM IS STRONGER AND MORE AMPLIFIED THAN THE GFS WITH THE
SHORTWAVE DROPPING INTO SOUTHEASTERN ONTARIO ON THE BACKSIDE OF
THE TROUGH. THE 00Z ECMWF AND BOTH THE 12Z GEM GLOBAL AND UKMET
ARE CLOSER TO THE NAM DEPTH WITH THIS WAVE...BUT NOT AS AMPLIFIED.
WILL RELY ON THEIR APPRECIABLE CONSENSUS WITH THE MID LEVEL
FORCING.
..SHORTWAVE ENERGY CROSSING THE OZARKS DAY 1
THE NAM IS CONSIDERABLY FARTHER NORTH THAN THE GFS WITH THIS
IMPULSE BY THE BEGINNING OF DAY 2...AND DEPICTS A ZONALLY ORIENTED
MID LEVEL VORTICITY AXIS. THE 00Z ECMWF OFFERS A REASONABLE
COMPROMISE BETWEEN THE RATHER DISPARATE MASS FIELDS OF THE 12Z NAM
AND GFS.
..SHORTWAVE CROSSING THE DAKOTAS AND MINNESOTA DAY 1
THE NAM IS STRONGER AND MORE AMPLIFIED THAN THE GFS WITH THIS
IMPULSE AS IT DIVES ACROSS THE UPPER MISSISSIPPI VALLEY AT THE
BEGINNING OF DAY 2. THE FATE OF THIS WAVE IS LINKED WITH THE
MOVEMENT OF THE UPSTREAM VORTEX OVER THE CANADIAN PRAIRIES...WHICH
THE NAM IS HANDLING DIFFERENTLY THAN THE OTHER RECENT
GUIDANCE...INCLUDING THE GFS...ECWMF...GEM GLOBAL...AND UKMET.
WILL THEREFORE RECOMMEND A SOLUTION MORE ALONG THE LINES OF THE
GFS HERE.
..VORTEX OVER SOUTHWESTERN CANADA
THE GFS IS CONSIDERABLY FARTHER SOUTH THAN THE NAM WITH THIS
SYSTEM...DIRECTING IT INTO NORTH DAKOTA EARLY DAY 3. THE 00Z
ECMWF AND BOTH THE 12Z GEM GLOBAL AND UKMET ARE CLUSTERED CLOSE TO
THE CURRENT GFS WITH THE TRACK OF THIS SYSTEM...SO WILL RELY ON
THEIR CONSIDERABLE CONSENSUS.
..SOUTHWEST MONSOON
THE GFS IS MORE INTENSE THAN THE NAM WITH THE IMPULSE CROSSING THE
FOUR CORNERS EARLY DAY 3...AND IS WEAKER WITH THE WAVE LIFTING
INTO SOUTHWESTERN ARIZONA AT THAT TIME. THE 00Z...LIKE THE 12Z
NAM AND GFS...DOES LIFT A MID LEVEL VORT INTO SOUTHWESTERN ARIZONA
EARLY DAY 3...SO THERE IS SOME CONSENSUS FOR THAT FEATURE...BUT
CANNOT FIND ANY SUPPORT ON THE WAY THE GFS HANDLES THE IMPULSE
NEAR THE FOUR CORNERS.
...500 MB FORECASTS AT
WWW.HPC.NCEP.NOAA.GOV/H5PREF/H5PREF.SHTML...
CISCO
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