997
FXUS10 KWNH 290646
PMDHMD
MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
245 AM EDT TUE OCT 29 2019
VALID OCT 29/0000 UTC THRU NOV 01/1200 UTC
...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR
INGEST...
00Z MODEL EVALUATION WITH PREFERENCES AND CONFIDENCE
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
..MID-LEVEL TROUGH CROSSING THE GREAT LAKES ON TUESDAY
..TRAILING FRONT FROM THE LOWER MS VALLEY TO THE NORTHEAST
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GENERAL MODEL BLEND
CONFIDENCE: ABOVE AVERAGE
SHORTWAVE ENERGY CURRENTLY LIFTING ACROSS THE MIDWEST WILL CROSS
THE GREAT LAKES OVER THE NEXT 24 HOURS AND ALLOW A WAVE OF LOW
PRESSURE TO QUICKLY CROSS THE REGION AND LIFT INTO ONTARIO/QUEBEC.
AN ATTENDANT COLD FRONT MEANWHILE WILL CROSS THE OH VALLEY, LOWER
GREAT LAKES AND MOVE INTO PARTS OF THE NORTHEAST BY TUESDAY NIGHT.
THE SOUTHWESTERN TAIL OF THE FRONT WILL STALL THOUGH OVER THE
LOWER MS VALLEY/WESTERN GULF COAST AS THE STRONG UPSTREAM HEIGHT
FALLS OVER THE CENTRAL ROCKIES BEGIN TO EJECT EAST OUT INTO THE
CENTRAL PLAINS. THERE IS ABOVE AVERAGE MODEL AGREEMENT AND
CONTINUITY SUCH THAT A GENERAL MODEL BLEND WILL SUFFICE FOR THIS
TIME FRAME.
..POWERFUL CLOSED LOW OVER THE INTERMOUNTAIN WEST ON TUESDAY
..ENERGY EJECTING EAST ACROSS THE PLAINS/MIDWEST WEDNESDAY
..COLD FRONT/SURFACE WAVE NEAR OH/TN VALLEYS BY THURSDAY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: BLEND OF THE 00Z UKMET/ECMWF AND 12Z ECENS MEAN
CONFIDENCE: AVERAGE...BECOMING BELOW AVERAGE BY THU/FRI
WITH STRONG RIDGING ALOFT ACROSS THE EASTERN PACIFIC, SHORTWAVE
ENERGY DROPPING SOUTH INTO THE NORTHERN/CENTRAL ROCKIES TUESDAY
WILL DIG VIGOROUSLY AND EVENTUALLY CLOSE OFF ACROSS UT/CO. THE 00Z
FV3-GFS CONTINUES TO STRUGGLE WITH THE TIMING OF ITS HEIGHT FALLS
EJECTING OUT ACROSS THE PLAINS AND MIDWEST WITH AN EMPHASIS ON THE
36 TO 60 HOUR TIME FRAME AS IT INSISTS ON A MORE PROGRESSIVE
SOLUTION COMPARED TO THE 00Z NAM AND 00Z NON-NCEP SUITE OF
GUIDANCE. THE FV3-GFS IS ALSO LIKELY MUCH TOO STRONG/AMPLIFIED AS
THE LATEST GEFS/ECENS MEANS FAVOR A LESS AMPLIFIED SYSTEM AND
CLOSER TO THE ECMWF IN PARTICULAR.
BETWEEN 60 AND 84 HOURS (THURSDAY TO EARLY FRIDAY), THE NAM TAKES
OVER FOR BEING THE STRONGEST SOLUTION BUT APPEARS TO BE TOO FAR
NORTH OVERALL WITH THE TRACK OF ITS CLOSED LOW FEATURE. THE GFS
BECAUSE OF ITS DEPTH EVENTUALLY SLOWS DOWN RELATIVE TO THE
REMAINING GUIDANCE AND ENDS UP ACTUALLY BEING THE SLOWEST SOLUTION
RELATIVE TO ITS IMPACTS ON THE GREAT LAKES AND NORTHEAST. DURING
THIS TIME, THE CMC STILL APPEARS TO BE A TAD TOO PROGRESSIVE AND
WEAK, BUT IT DID TREND AT LEAST A LITTLE STRONGER WITH THE 00Z
CYCLE. THE UKMET FOR ITS PART TRENDED STRONGER AND FASTER AND
ACTUALLY IS RATHER CLOSE TO THE ECMWF FOR MOST OF THE SHORT-RANGE
PERIOD. BASED ON BETTER RUN TO RUN CONTINUITY, THE PREFERENCE WILL
INCLUDE A BLEND OF THE 00Z ECMWF AND 12Z ECENS MEAN, BUT WILL ALSO
INCORPORATE THE 00Z UKMET GIVEN ITS TREND TOWARD THE ECMWF CAMP.
THE 00Z GEFS MEAN FOR ITS PART SUPPORTS THE TIMING OF THIS CAMP,
BUT IS JUST NOT AS DEEP.
..NEXT UPPER TROUGH/FRONT OVER THE PLAINS BY FRIDAY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GENERAL MODEL BLEND
CONFIDENCE: ABOVE AVERAGE
THE MODELS ADVERTISE A NEW UPPER TROUGH DIGGING DOWN ACROSS THE
CENTRAL/NORTHERN PLAINS LATE THURSDAY AND INTO FRIDAY ALONG WITH A
NEW COLD FRONT DROPPING SOUTHEAST FROM CANADA. MODEL SPREAD IS
MINIMAL WITH THIS NEXT SYSTEM, SO A GENERAL MODEL BLEND WILL BE
PREFERRED FOR THE TIME BEING.
MODEL TRENDS AT WWW.WPC.NOAA.GOV/HTML/MODEL2.HTML
500 MB FORECASTS AT WWW.WPC.NOAA.GOV/H5PREF/H5PREF.SHTML
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