Prognostic Meteorological Discussion
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5
000
FXUS10 KWNH 221830
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
229 PM EDT TUE APR 22 2014

VALID APR 22/1200 UTC THRU APR 26/0000 UTC

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

12Z MODEL EVALUATION...INCLUDING THE NAM/GFS/UKMET/GEM AND ECMWF


...MID LEVEL TROUGH/CLOSED LOW IMPACTING NEW ENGLAND THROUGH
MIDWEEK...

PREFERENCE: NON-NAM CONSENSUS
CONFIDENCE: ABOVE AVERAGE

THE 12Z NAM IS A LITTLE SLOWER AND DEEPER THAN THE GLOBAL MODEL
CONSENSUS WITH THE NRN STREAM HEIGHT FALLS THAT DIG SEWD ACROSS
NEW ENGLAND THIS PERIOD. ALL OF THE MODELS SUGGEST THE ENERGY WILL
GO NEG-TILT WHILE CROSSING NEW ENGLAND ON WED AND THEN CLOSE OFF
JUST OFFSHORE OF NEW ENGLAND ON THURS. THE NAM DOES COME INTO
BETTER AGREEMENT WITH THE GLOBAL MODEL CONSENSUS AFTER THE ENERGY
EXITS EAST AND WELL OFFSHORE...BUT WILL PREFER A NON-NAM CONSENSUS
ATTM.


...LARGE TROUGH MOVING INTO THE WEST TODAY...CROSSING THE NORTHERN
STATES BY THURSDAY/FRIDAY...

PREFERENCE: 00Z ECMWF
CONFIDENCE: BELOW AVERAGE

THE MODELS ARE STILL SHOWING INCONSISTENCIES RUN TO RUN ON THE
TIMING AND DEPTH OF THE TROUGH/CLOSED LOW EVOLUTION OVER THE NEXT
COUPLE OF DAYS THAT EJECTS OUT OF THE NORTHWEST AND CROSSES THE
CNTRL/NRN PLAINS AND MIDWEST BY THURSDAY. THE 12Z NAM IS A LITTLE
DEEPER THAN THE MULTI-MODEL CONSENSUS...WITH THE 12Z UKMET THE
WEAKEST SOLN. THE 12Z GEM BECOMES A SLOW OUTLIER BY THE END OF THE
PERIOD...WITH THAT MODEL HOLDING MUCH MORE ENERGY BACK TO THE WEST
OVER THE NRN PLAINS AND UPR MIDWEST WHEREAS MOST OF THE MODELS
SUPPORT THE ENERGY CROSSING THE GREAT LAKES REGION BY THEN. SFC
AND ALOFT...THE 00Z ECMWF TENDED TO HAVE THE STRONGER ENSEMBLE
SUPPORT WHICH INCLUDED THE 00Z ECENS MEAN AND 06Z GEFS MEAN. THE
NEW 12Z ECMWF THOUGH IS A BIT WEAKER THAN ITS PREV RUN...AND IS
ALSO A LITTLE FARTHER NORTH ESP ALOFT WITH THE TROUGH/CLOSED LOW
TRACK. THE 12Z GFS HAS ITS TROUGH/CLOSED LOW FARTHER SOUTH THAN
ANY OTHER MODEL BY THURS AND FRI...ALTHOUGH IT DOES HAVE SUPPORT
FROM THE 12Z GEFS MEAN. GIVEN THE FAIR AMT OF SPREAD...AND LACK OF
CONTINUITY...CONFIDENCE IS LIMITED...BUT WILL MAINTAIN THE PREV
PREFERENCE ATTM WHICH WAS THE 00Z ECMWF.


...BROAD TROUGH REACHING THE PACIFIC NORTHWEST THURSDAY...

PREFERENCE: NON-NAM CONSENSUS
CONFIDENCE: ABOVE AVERAGE

OVERALL THERE IS RELATIVELY GOOD MODEL AGREEMENT ON THE LARGE
SCALE WITH THE NEXT TROUGH AXIS MOVING IN OFF THE PACIFIC OCEAN
AND CROSSING THE WEST COAST LATER THIS WEEK. THE 12Z NAM IS
PERHAPS A LITTLE TOO STRONG ALOFT...ESP OVER THE PAC
NORTHWEST...BUT THE REMAINING MODELS CLUSTER TOGETHER RATHER WELL
FOR DEPTH...AND ACTUALLY THERE IS VERY GOOD AGREEMENT WITH ALL OF
THE MODELS REGARDING THE TIMING DETAILS OF THE TROUGH. WILL PREFER
A NON-NAM CONSENSUS ATTM.


...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
$$





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.