073
FXUS10 KWNH 110659
PMDHMD
MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
258 AM EDT SAT APR 11 2020
VALID APR 11/0000 UTC THRU APR 14/1200 UTC
...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR
INGEST...
00Z MODEL EVALUATION...WITH PREFERENCES AND CONFIDENCE
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
..CLOSED LOW EXITING THE SOUTHWEST
..ENERGY EJECTING TOWARD THE LOWER MS VALLEY BY SUNDAY
..POWERFUL SURFACE LOW OVER THE GREAT LAKES BY MONDAY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: 00Z GFS/ECENS/GEFS BLEND
CONFIDENCE: AVERAGE...THROUGH 48 HOURS
BECOMING BELOW AVERAGE...AFTER 48 HOURS
07Z UPDATE: THE 00Z ECMWF CONTINUED TO SHOW A NORTHWEST SOLUTION
COMPARED TO THE REST OF THE MODEL GUIDANCE FOR DAY 2/3 AS THE LOW
TRACKS FROM THE MID-MS TO LOWER GREAT LAKES REGIONS. THE 00Z ECMWF
IS ALMOST IDENTICAL IN LOW TRACK, MAYBE A TAD TO THE SOUTH, TOWARD
THE ECENS MEAN. THE 00Z UKMET APPEARS TO BE A SOUTHERN OUTLIER
WHILE THE CMC/NAM ARE TOO FAR NORTH AT THIS TIME. A SOLUTION
TOWARD THE ECENS AND GEFS MEANS SEEMS LIKE THE BEST APPROACH AT
THIS TIME, WHICH IS BOOK-ENDED BY THE DETERMINISTIC GFS/ECMWF.
---PREVIOUS DISCUSSION---
THE LARGE, SLOW-MOVING CUT-OFF SOUTHERN STREAM LOW OVER SOUTHERN
CALIFORNIA WILL GRADUALLY MOVE TOWARD SOUTHERN AZ/NM LATER TODAY
AND THEN OPEN UP INTO A PROGRESSIVE SHORTWAVE ACROSS THE SOUTHERN
PLAINS BY EARLY SUNDAY. BY LATE SUNDAY, THIS ENERGY WILL BEGIN TO
TAKE ON A NEGATIVE TILT OVER THE LOWER MS VALLEY AND QUICKLY REACH
THE OH VALLEY BY EARLY MONDAY. THE ENERGY COUPLED WITH INCREASING
INFLUENCE FROM A STRONG NORTHERN STREAM TROUGH AMPLIFYING OVER THE
UPPER MIDWEST SUNDAY AND MONDAY WILL LEAD THE WAY FOR A POWERFUL
SURFACE CYCLONE TO LIFT OVER LOWER MI ON MONDAY. THE MOST RECENT
GUIDANCE CONTINUES TO ZERO IN ON A SOLUTION FOR THE DEPTH AND
TRACK OF THE SURFACE LOW AS IT MOVES FROM THE LOWER MS VALLEY TO
LOWER MICHIGAN. ENSEMBLE LOW TRACK SPREAD HAS LESSENED IN THE LAST
24 HOURS AND NOW OUTSIDE OF THE NAM (TOO FAST) AND CMC (TOO FAR
NORTHWEST), THE DETERMINISTIC GFS/UKMET OFFER FAIRLY REASONABLE
SOLUTIONS WITH THEIR MASS FIELDS, THOUGH THE 12Z ECMWF WAS LESS
PREFERRED FOR ITS NORTHWEST JUMP. FOR NOW, WILL SIDE ON THE
FURTHER SOUTH GFS/UKMET SOLUTION AND ALSO THE ECENS/GEFS. BUT IT'S
ADMITTEDLY A LOWER CONFIDENCE FORECAST BEYOND 48-60 HOURS AND
THERE COULD BE A TREND TO THE NORTHWEST LIKE WHAT THE 12Z ECMWF
SUGGESTS.
..AMPLIFYING UPPER TROUGH OVER THE NORTHERN U.S. BY MONDAY
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GENERAL MODEL BLEND
CONFIDENCE: ABOVE AVERAGE
THE MODELS BRING AMPLIFYING SHORTWAVE/JET ENERGY SOUTHEASTWARD
FROM THE SOUTHERN COAST OF AK AND THE ADJACENT YUKON TERRITORY
DOWN ACROSS SOUTHWEST CANADA AND OUT ACROSS THE NORTHERN ROCKIES
AND NORTHERN PLAINS BY SUNDAY. BY MONDAY, THIS ENERGY WILL AMPLIFY
INTO A DEEP LONGWAVE TROUGH OVER THE NORTHERN U.S. THAT WILL
GRADUALLY PHASE WITH THE AFOREMENTIONED SOUTHERN STREAM ENERGY
EJECTING ACROSS THE SOUTH AND LIFTING TOWARD THE GREAT LAKES
REGION. THE MODELS ARE IN GOOD AGREEMENT WITH THE DETAILS OF THE
LONGWAVE TROUGH EVOLUTION. SO, A GENERAL MODEL BLEND WILL BE
PREFERRED WITH THIS.
MODEL TRENDS AT WWW.WPC.NCEP.NOAA.GOV/HTML/MODEL2.SHTML
500 MB FORECASTS AT WWW.WPC.NCEP.NOAA.GOV/H5PREF/H5PREF.SHTML
TAYLOR
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page