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000
FXUS10 KWNH 230635
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
235 AM EDT THU MAY 23 2013

VALID MAY 23/0000 UTC THRU MAY 26/1200 UTC

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


FINAL 00Z MODEL EVALUATION...INCLUDING THE UKMET/GEM GLOBAL AND
THE ECMWF

NO SIGNIFICANT INITIALIZATION ERRORS ARE SEEING IMPACTING THE
SHORT RANGE FORECAST.


...DEEP UPPER TROUGH/CLOSED LOW OVER THE NORTHWEST...

PREFERENCE: NON-GEM GLOBAL CONSENSUS
CONFIDENCE: AVERAGE

THE LATEST GUIDANCE IS IN VERY GOOD AGREEMENT WITH THE DETAILS OF
THIS DEEP UPPER LOW THROUGH FRI...AND THEN THERE IS A GRADUAL
INCREASE IN SPREAD THEREAFTER AS THE MODELS SHOW SOME DISAGREEMENT
WITH HOW UPSTREAM SHORTWAVE ENERGY DIGS IN FROM THE GULF OF AK.
OVERALL...THE 00Z MODELS ARE CLUSTERING BETTER NOW AND AGREE THAT
THERE SHOULD BE A CLOSED LOW EVOLVING OVER THE PAC NW EARLY IN THE
PERIOD AND THEN REORGANIZING OVER SWRN CANADA INVOF SRN
B.C./ALBERTA IN AN ELONGATED FASHION ON SAT WITH LIKELY TWO
DISTINCT CENTERS AS SHORTWAVE ENERGY PIVOTS AROUND A MEAN CENTER.
THE 00Z GEM GLOBAL THOUGH INSISTS ON A SEPARATE CLOSED LOW
DEVELOPING OFFSHORE OF THE PAC NW BY THE END OF THE PERIOD AS
ENERGY DROPS SEWD FROM THE GULF OF AK. THE GEM GLOBAL IS NOW
OVERALL AN OUTLIER SOLN. WILL THEREFORE SUGGEST A NON-GEM GLOBAL
CONSENSUS ATTM GIVEN THAT THE REMAINING MODEL GUIDANCE IS RATHER
WELL CLUSTERED.


...DEEP UPPER TROUGH/CLOSED LOW MOVING FROM THE MIDWEST TO THE
NORTHEAST...

PREFERENCE: BLEND OF THE 00Z GFS/00Z UKMET
CONFIDENCE: AVERAGE

THE UPPER TROUGH ATTM OVER THE MIDWEST WILL BE DIGGING SEWD
THROUGH THE OH VLY AND INTO THE MID-ATLANTIC REGION THROUGH FRI
AND IS LIKELY TO CLOSED OFF OVER THIS REGION ON SAT AS ADDITIONAL
UPSTREAM SHORTWAVE ENERGY DIGGING IN FROM THE GRT LAKES REGION
ARRIVES AND INTENSIFIES THE HT FALLS. THE HT FALLS ARE THEN
EXPECTED TO PIVOT AND BECOME NEG TILTED SAT INTO SUN WITH THE
ENERGY LIFTING UP ACROSS NEW ENGLAND. THE 00Z MODELS HAVE COME
INTO BETTER AGREEMENT WITH THE DETAILS OF THE HT FALL EVOLUTION
AND ARE WELL CLUSTERED NOW THROUGH FRI AND SAT...THEREAFTER THE
SPREAD INCREASES. THE UKMET WHICH HAD BEEN AN OUTLIER SOLN
PREVIOUSLY IS NOW IS VERY GOOD AGREEMENT OVERALL WITH THE 00Z GFS.
THE ECMWF WHICH HAD BEEN FARTHER SOUTH BEFORE WITH ITS CLOSED LOW
TRACK HAS TRENDED A LITTLE FARTHER NORTH IN LINE WITH THE
CONSENSUS. HOWEVER...THE 00Z ECMWF DOES STILL APPEAR TO BE A TAD
OF A DEEP OUTLIER...AT LEAST ALOFT. THE 00Z NAM ON THE OTHER HAND
IS THE WEAKEST SOLN AND TAKES ITS ENERGY OFF TO THE NORTHEAST MORE
PROGRESSIVELY THAN ANY OTHER MODEL. THE STRONGEST MODEL CLUSTER IS
REFLECTED BY THE GFS/UKMET CAMP NOW.


...MODEL TREND GRAPHICS AT
WWW.WPC.NCEP.NOAA.GOV/HTML/MODEL2.SHTML...
...500 MB FORECASTS AT WWW.WPC.NCEP.NOAA.GOV/H5PREF/H5PREF.SHTML...

ORRISON

$$