Prognostic Meteorological Discussion
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6

000
FXUS10 KWNH 060646
PMDHMD

MODEL DIAGNOSTIC DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
245 AM EDT MON JUL 06 2015

VALID JUL 06/0000 UTC THRU JUL 09/1200 UTC

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

00Z MODEL EVALUATION...INCLUDING THE NAM/GFS/UKMET/CMC AND ECMWF

...UPPER TROUGH MOVING THROUGH CENTRAL/EASTERN CANADA MON/TUES...
...COLD FRONT CROSSING THE CENTRAL PLAINS/GREAT LAKES/NORTHEAST...

PREFERENCE: BLEND OF THE 00Z GFS AND 00Z ECMWF
CONFIDENCE: AVERAGE

MASS FIELD DIFFERENCES ALOFT WITH THE TROUGH PROGRESSION ARE
RATHER MINIMAL...BUT THERE IS A BIT MORE SPREAD AT THE SURFACE
WITH THE FRONT. THE 00Z UKMET/00Z CMC SOLUTIONS ARE QUICKER TO
BRING THE FRONT THROUGH THE NORTHEAST TUES NIGHT...WITH THE 00Z
NAM BECOMING THE SLOWEST. THE 00Z GFS AND 00Z ECMWF ARE MORE
STRONGLY CLUSTERED...AND A BLEND OF THESE TWO SOLUTIONS WILL BE
PREFERRED.


...UPPER TROUGH CROSSING THE UPPER OHIO VALLEY AND CENTRAL
APPALACHIANS...

PREFERENCE: NON-UKMET CONSENSUS
CONFIDENCE: ABOVE AVERAGE

MOST OF THE MODELS SHOW REASONABLE AGREEMENT HERE...BUT THE 00Z
UKMET REMAINS SLIGHTLY WEAKER AND FASTER THAN THE AGREEABLE AND
NOW TIGHTLY CLUSTERED DETERMINISTIC/ENSEMBLE CONSENSUS.


...SHORTWAVE CROSSING THE SOUTHWEST AND CENTRAL/SOUTHERN PLAINS...
...DEVELOPING SURFACE LOW LIFTING TOWARD THE MIDWEST...

PREFERENCE: BLEND OF THE 00Z GFS AND 00 ECMWF
CONFIDENCE: AVERAGE

A MID LEVEL SHORTWAVE EMBEDDED WITHIN THE SOUTHWEST FLOW AHEAD OF
THE APPROACHING WEST COAST UPPER LOW IS FORECAST TO ADVANCE EAST
OUT INTO THE CENTRAL AND SOUTHERN HIGH PLAINS TUES AND WED AND
AMPLIFY SOMEWHAT. THIS WILL ALSO DEVELOP AND AREA OF LOW PRESSURE
NORTH OF THE RED RIVER VALLEY THAT WILL ADVANCE NORTHEAST TOWARD
THE MIDWEST BY WED. THE 00Z NAM IS THE SLOWEST/STRONGEST
SOLUTION...WITH THE REMAINING MODELS CLUSTERED AROUND A TAD MORE
PROGRESSIVE AND SLIGHTLY WEAKER TROUGH AXIS. AT THE
SURFACE...THERE IS REASONABLY GOOD MODEL CLUSTERING WITH THE LOW
CENTER...BUT THE 00Z NAM DOES LAG THE MULTI-MODEL CONSENSUS AS THE
LOW REACHES THE MIDWEST. THE 00Z UKMET ALSO TENDS TO BE A BIT
DEEPER THAN THE CONSENSUS BY THE END OF THE PERIOD WHICH IS TIED
IN WITH A RELATIVELY STRONGER TROUGH AXIS ALOFT. THE STRONGER
MODEL CLUSTERING AT THIS POINT FAVORS A BLEND OF THE 00Z GFS AND
00Z ECMWF...AND THAT WILL BE PREFERENCE.


...EASTERN PACIFIC UPPER LOW HOVERING WEST OF CALIFORNIA THROUGH
WED...

PREFERENCE: GENERAL MODEL COMPROMISE
CONFERENCE: ABOVE AVERAGE

ALL OF THE LATEST DETERMINISTIC GUIDANCE TAKES AN UPPER LOW OVER
THE EASTERN PACIFIC CURRENTLY CENTERED NEAR 35N 130W SLOWLY
EASTWARD TOWARD CALIFORNIA THROUGH THE MIDDLE OF THE WEEK WITH
REASONABLE AGREEMENT. A GENERAL MODEL COMPROMISE WILL BE PREFERRED.


...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.