222
FXUS10 KWNH 081900
PMDHMD
MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
159 PM EST WED JAN 08 2020
VALID JAN 08/1200 UTC THRU JAN 12/0000 UTC
...SEE NOUS42 KWNO (ADMNFD) FOR THE STATUS OF THE UPPER AIR
INGEST...
12Z MODEL EVALUATION WITH FINAL PREFERENCES AND CONFIDENCE
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
..INITIAL SHORTWAVE CROSSING THE PACIFIC NORTHWEST
..ENERGY ADVANCING EAST ACROSS THE NORTHERN PLAINS/MIDWEST
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GENERAL MODEL BLEND
CONFIDENCE: ABOVE AVERAGE
THE MODELS SHOW SIMILARLY WITH THIS SYSTEM WITH ONLY MINOR
DIFFERENCES REMAINING IN THE LATEST MODEL GUIDANCE. NO SIGNIFICANT
DIFFERENCES WERE NOTED WITH THE 12Z ECMWF/UKMET/CMC COMPARED TO
THEIR PREVIOUS 00Z CYCLES.
..SHORTWAVE AMPLIFYING ACROSS THE FOUR CORNERS/HIGH PLAINS
..DEEPENING SURFACE LOW OVER THE LOWER MS VALLEY FRI/SAT
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: BLEND OF THE 12Z NAM/12Z ECMWF/12Z UKMET
CONFIDENCE: AVERAGE
A SHORTWAVE TROUGH IS EXPECTED TO CROSS THE WEST COAST EARLY
THURSDAY MORNING AND AMPLIFY ACROSS THE SOUTHWEST THROUGH THURSDAY
NIGHT. A NORTHERN STREAM COMPONENT WILL TRACK EAST THROUGH THE
NORTH-CENTRAL U.S. BEFORE LIFTING INTO CANADA BY SATURDAY
AFTERNOON. THERE IS GOOD AGREEMENT WITH THE NORTHERN PORTION BUT
TIMING DIFFERENCES SHOW UP WITH THE SOUTHERN, MORE POWERFUL
SHORTWAVE WHICH SHOULD EJECT OUT INTO THE SOUTHERN PLAINS FRIDAY
NIGHT.
WITH A +1 TO +2 STANDARDIZED ANOMALY 500 MB RIDGE SLOWLY SPREADING
NORTH FROM THE CARIBBEAN INTO THE WESTERN
ATLANTIC OFF OF THE EAST COAST THROUGH SATURDAY, THE FASTER 12Z
GFS SEEMS TO BE A LOWER PROBABILITY SCENARIO. HOWEVER, AN UPSTREAM
SHORTWAVE TROUGH WILL ACT AS A KICKER, PREVENTING TOO MUCH IN THE
WAY OF A SLOW DOWN ACROSS THE SOUTHERN PLAINS. CURRENTLY, THE ONLY
TRENDS OBSERVED IN THE ENSEMBLE CYCLES IS FOR MORE AMPLIFICATION
VERSUS A FASTER OR SLOWER TREND. THE ENSEMBLE DISTRIBUTION SHOWS
THE 12Z GFS ON THE FAST END WITH THE 12Z CMC ON THE SLOW END OF
THE LATEST GUIDANCE. THE 00Z ECMWF MEAN IS SLIGHTLY AHEAD OF THE
00Z AND 12Z ECMWF, SO A BLEND BETWEEN THE 12Z ECMWF, 12Z UKMET AND
FASTER 12Z NAM IS PREFERRED AT THIS TIME, ATTEMPTING TO REPRESENT
A MIDDLE GROUND SOLUTION. A SUBTLE SLOWER TREND IN THE 12Z ECMWF,
FASTER TREND IN THE 12Z UKMET AND A MORE NOTABLE SLOWER TREND IN
THE 12Z CMC WAS NOTED RELATIVE TO THEIR PREVIOUS 00Z CYCLES.
..NEXT UPPER TROUGH OVER THE NORTHWEST BY SAT
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PREFERENCE: GENERAL MODEL BLEND
CONFIDENCE: ABOVE AVERAGE
THE DETERMINISTIC AND ENSEMBLE GUIDANCE SHOWS REASONABLE AGREEMENT
WITH THIS SYSTEM. MINOR AMPLITUDE DIFFERENCES SHOW UP BY SATURDAY
WITH THE 12Z ECMWF/UKMET TRENDED SLIGHTLY WEAKER OUT WEST COMPARED
TO THEIR PREVIOUS 00Z CYCLES. GIVEN DIFFERENCES ARE MINOR THROUGH
THE END OF THE SHORT RANGE (00Z/12), A GENERAL MODEL BLEND WILL BE
PREFERRED AT THIS TIME.
MODEL TRENDS AT WWW.WPC.NCEP.NOAA.GOV/HTML/MODEL2.HTML
500 MB FORECASTS AT WWW.WPC.NCEP.NOAA.GOV/H5PREF/H5PREF.SHTML
OTTO
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page