Prognostic Meteorological Discussion
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000
FXUS02 KWBC 061632
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1131 AM EST SAT FEB 06 2016

VALID 12Z TUE FEB 09 2016 - 12Z SAT FEB 13 2016

...SNOW REMAINS A POSSIBILITY FOR COASTAL AREAS OF THE NORTHEAST
AND NORTHERN MID-ATLANTIC STATES EARLY NEXT WEEK...


GENERAL FLOW PATTERN...

HIGHLY AMPLIFIED FLOW OVER THE CONUS AT THE START OF THE FORECAST
PERIOD WILL GRADUALLY FLATTEN THROUGHOUT NEXT WEEK BUT SHOULD
STILL FEATURE MEAN RIDGING IN THE WEST AND TROUGHING IN THE EAST.
WITHIN THE LARGE SCALE FLOW...A SURFACE LOW EXPECTED TO DEEPEN OFF
THE NORTHERN MID-ATLANTIC COAST WILL LIFT UP THE EASTERN SEABOARD
ON TUESDAY AND THEN THE FOCUS WILL SHIFT TO A POTENTIAL CLIPPER
SYSTEM DROPPING THROUGH THE UPPER MIDWEST LATER IN THE WEEK.  THE
WEST WILL REMAIN RATHER QUIET UNTIL LATE NEXT WEEK WHEN THE RIDGE
SHIFTS SLIGHTLY EAST TOWARDS THE DIVIDE AND AN UPPER TROUGH BEGINS
PROGRESSING INLAND.


MODEL EVALUATION/PREFERENCES...

THE FORECAST STARTED WITH A GENERAL COMPROMISE BETWEEN A
RELATIVELY AGREEABLE 00Z GFS/ECMWF/GEFS MEAN/ECMWF ENSEMBLE MEAN.
SLIGHTLY LESS WEIGHT WAS GIVEN TO THE GFS SINCE IT REMAINED ON THE
FASTER SIDE OF MODEL SPREAD WITH LIFTING A SURFACE LOW AWAY FROM
THE NORTHERN MID-ATLANTIC COAST ON TUESDAY...BUT NOISE IN THE
ENSEMBLE MEMBERS STILL SUGGESTS A LOT OF UNCERTAINTY WITH THIS
SYSTEM.  OTHER AREAS OF UNCERTAINTY IN THE FORECAST INCLUDE THE
EXACT AMPLITUDE OF A BROAD TROUGH OVER THE EASTERN U.S. LATE NEXT
WEEK AS WELL AS THE TIMING/EVALUATION OF AN UPPER TROUGH SLIDING
INTO THE WESTERN U.S. NEXT SATURDAY.


SENSIBLE WEATHER HIGHLIGHTS...

THE POTENTIAL REMAINS FOR WIDESPREAD LIGHT TO MODERATE SNOWS OVER
PORTIONS OF THE CENTRAL APPALACHIANS..MID-ATLANTIC...AND NORTHEAST
WITH A SURFACE LOW LIFTING AWAY FROM THE COAST ON TUESDAY...BUT A
COMPLICATED UPPER/SURFACE PATTERN EVOLUTION LOWERS CONFIDENCE IN
PRECIPITATION AND P-TYPE DETAILS.  BEHIND THIS SYSTEM...CYCLONIC
FLOW IN CONCERT WITH A CLIPPER PASSAGE WILL MAINTAIN SEVERAL DAYS
OF LAKE EFFECT SNOW, ESPECIALLY FOR THE UPPER PENINSULA OF
MICHIGAN AND WESTERN LOWER MICHIGAN.  GENERAL TROUGHING WILL KEEP
TEMPERATURES BELOW NORMAL FOR MUCH OF THE EASTERN HALF OF THE
NATION.

MEAN RIDGING WILL SUPPORT ABOVE NORMAL TEMPERATURES FOR MUCH OF
THE WESTERN U.S...WITH RECORD HIGHS AND RECORD HIGH MINIMUM
TEMPERATURES A POSSIBILITY FOR SOME LOCATIONS.  CONDITIONS SHOULD
STAY DRY UNTIL THE RIDGE SLIDES SLIGHTLY EAST AND AN UPPER TROUGH
PROGRESSES INLAND OVER THE NORTHWEST LATE NEXT WEEK.


GERHARDT

$$




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