Prognostic Meteorological Discussion
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000
FXUS02 KWBC 201600
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1200 PM EDT MON OCT 20 2014

VALID 12Z THU OCT 23 2014 - 12Z MON OCT 27 2014

WPC MEDIUM RANGE SURFACE FRONTS/PRESSURES AND 500 MB PROGS HAVE
BEEN PRIMARILY DERIVED FROM THE 00 UTC NAEFS MEAN. THE NAEFS MEAN
OVERALL OFFERS COMPROMISE FLOW AMPLITUDE/PROGRESSION OVER THE NEXT
WEEK IN BETWEEN THE SLOWER ECMWF ENSEMBLE MEAN AND RECENT FASTER
GEFS MEANS. THIS IS CONSISTENT WITH RECENT ENSEMBLE BIASES. PREFER
AN ENSEMBLE MEAN FORECAST APPROACH IN LUE OF DETERMINISTIC MODELS
THAT OFFER LESS THAN STELLAR RUN-RUN CONTINUITY WITH SMALL-MID
SCALE EMBEDDED SYSTEMS.

GUIDANCE REASONABLY LIFTS A LEAD CLOSED VORTEX AND SOME MODERATLY
HEAVY WRAPPED-BACK COLD RAINS SLOWLY FROM THE NERN US TO THE
CANADIAN MARITIMES THU-SAT...WITH COOLING HIGH PRESSURE IN ITS
WAKE OVER THE EAST-CENTRAL US. A WAVY TRAILING FRONT LINGERS BACK
NEAR FL AND THE GULF OF MEXICO/MEXICO THAT MAY COMBINE WITH
TROPICAL MOISTURE AND NHC LOW  POTENTIAL TO FAVOR A HEAVY PCPN
THREAT FOR S-CENTRAL FL LATE WEEK INTO NEXT WEEK. AN UNCERTAIN
ENERGY SPLIT DIGGING INTO THE E-CENTRAL US BEHIND THIS CLOSED LOW
WOULD EFFECT ANY STREAM INTERACTIONS WITH THE LOW LATITUDES TO BE
DETERMINED.

MEANWHILE...IMPULSE ENERGY RUNNING INLAND FROM A MEAN ERN PACIFIC
MID-UPPER LEVEL TROUGH POSITION ACROSS THE NORTHWEST AND OUT OVER
S-CENTRAL CANADA AND DOWN INTO THE CENTRAL THEN ERN US NRN TIER
STATES WITH SOME ORGANIZED LOW DEVELOPMENT AND LEAD PCPN AND
POST-FRONTAL COOLING...ALL IN A DEAMPLIFYING FLOW PATTERN WITH
TIME.

UPSTREAM...POTENT AND UNSETTLING ENERGIES ASSOCIATED WITH THE
HIGHLY AMPLIFIED MEAN ERN PACIFIC MID-UPPER LEVEL TROUGH LATE WEEK
ARE EXPECTED TO PUNCH MORE ERNESTLY INLAND AND SPREAD PCPN ACROSS
THE WRN US THIS WEEKEND. THIS SYSTEM ENERGY REACHES THE PLAINS BY
EARLY NEXT WEEK AS A POTENTIALLY ORGANIZED KICKER SYSTEM
ASSOCIATED WITH THE EXTRATROPICAL REMAINS OF CURRENT TROICAL STORM
ANA COULD BECOME INFUSED INTO ERN PACIFIC MID-LATITUDE FLOW.

SCHICHTEL

$$





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