Weerwoord | NOAA!

MODEL ISSUES ARE SIGNIFICANT THIS PERIOD. THE 00Z ECMWF BECOMES
VERY FAST WITH A SHORTWAVE MOVING THROUGH THE PLAINS MONDAY, AND
EVEN THOUGH ITS PATTERN ALOFT RESEMBLES THE ENSEMBLE MEAN SOLUTION
LATE NEXT WEEK, ITS PRESSURE PATTERN HAS BEEN SO CONTAMINATED BY
THIS QUICK-MOVING SHORTWAVE ACROSS THE EAST AND WESTERN ATLANTIC,
ITS SOLUTION COULD NOT BE USED. THE 00Z GFS BROKE DOWN THE
WESTERN RIDGE WEDNESDAY MORNING BY USING A FORMERLY CLOSED LOW TO
DO SO, AND DOES NOT CONVERGE WITH THE REMAINDER OF THE GUIDANCE
UNTIL DECEMBER 1ST, SO ITS SOLUTION WAS NOT USED EITHER.

Indeed its all round carnage with no model surviving criticism:

THE CANADIAN SOLUTION IS ON THE SLOW SIDE OF THE
12Z GLOBAL ENSEMBLE ENVELOPE TO BOOT, AND CONSIDERING THE
RELATIVELY LOW AMPLITUDE FLOW, ITS SOLUTION SHOULD BE QUICKER AND
POSSIBLY WEAKER HERE, SO ITS SOLUTION WAS NOT BE USED EITHER.

And finally:

PER THE ABOVE, THE PRESSURES USED A 00Z UKMET TEMPLATE THROUGH
TUESDAY BEFORE TRANSITIONING TO A 50/50 BLEND OF THE 00Z GEFS/12Z
ECMWF ENSEMBLE MEAN SOLUTIONS. THE 00Z UKMET SOLUTION WAS NOT
PERFECT EITHER, SHOWING QUICKER PROGRESSION THAN ANTICIPATED BY
THE ENSEMBLE LOW CLUSTERING ACROSS THE EAST AND WESTERN ATLANTIC,
SO SHIFTED ITS LOW PRESSURE CENTER TOWARDS 12Z GLOBAL ENSEMBLE
CLUSTERING TUESDAY AND WEDNESDAY. CONSIDERING THE DETERMINISTIC
MODEL SPREAD THIS PERIOD, THE RELATIVELY LOW AMPLITUDE FLOW ACROSS
THE LOWER 48 UNITED STATES, AND THE LACK OF AN OVERALL GOOD
DETERMINISTIC MODEL CHOICE, CONFIDENCE IS BELOW AVERAGE IN THIS
PREFERENCE.

The aviation forecast also talks about the ECM:

TROUGHING MOVING ACROSS THE NORTHWEST/HIGH PLAINS SUNDAY/MONDAY
===============================================================
PREFERENCE: NON-ECMWF COMPROMISE WITH AVERAGE CONFIDENCE

THE 00Z ECMWF SHOWS THE MOST PROGRESSIVE SOLUTION WITH THIS SYSTEM
(EVEN WHEN COMPARED TO THE GEFS/SREF/ECMWF ENSEMBLE MEANS), WHILE
THE REMAINDER OF THE GUIDANCE IS SOMEWHAT SHARPER AND SLOWER. AN
AMPLIFIED RIDGE LIES UPSTREAM OFFSHORE THE WEST COAST, WHICH
ARGUES FOR A SLOWER/DEEPER SOLUTION. A NON-ECMWF COMPROMISE IS
PREFERRED HERE WITH AVERAGE CONFIDENCE CONSIDERING ITS PROGRESSIVE
NATURE.