Prognostic Meteorological Discussion
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FXUS01 KWBC 260839
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
339 AM EST MON JAN 26 2015

VALID 12Z MON JAN 26 2015 - 12Z WED JAN 28 2015

...A MAJOR WINTER STORM TO AFFECT THE NORTHEASTERN U.S. ON
MONDAY/TUESDAY...

...VERY MILD TEMPERATURES TO CONTINUE OVER THE CENTRAL STATES...

...WET WEATHER EXPECTED ACROSS THE DESERT SOUTHWEST...


AT THIS POINT IN TIME, A CLIPPER SYSTEM IS WEAKENING OVER THE OHIO
VALLEY AND CENTRAL APPALACHIANS WHICH WILL EVENTUALLY GIVE WAY TO
A POTENT COASTAL STORM. A GENERAL REGION OF 2 TO 4 INCHES OF SNOW
SHOULD SPREAD OVER THE MUCH OF THE MID-ATLANTIC REGION GIVEN THE
LIMITED MOISTURE AND DECAYING NATURE OF THE INITIAL SYSTEM.
HOWEVER, AS THE UPPER TROUGH DIGS ACROSS THE CAROLINAS, IT WILL
ATTAIN A FAVORABLE ORIENTATION FOR RAPID STRENGTHENING. BY MONDAY
EVENING AND INTO THE OVERNIGHT HOURS, COASTAL CYCLOGENESIS WILL
COMMENCE EAST OF THE DELMARVA WITH HEAVY PRECIPITATION SPREADING
NORTH AND WEST OF THE LOW TRACK. UNLIKE THE SYSTEM THIS PAST WEEK
WHICH HAD LIMITED ACCESS TO COLD AIR, A PRONOUNCED SURFACE RIDGE
TO THE NORTH WILL SUPPLY SUFFICIENT SUBFREEZING AIR TO THE
NORTHEASTERN U.S. THIS WILL ALLOW SNOW TO BE THE DOMINANT
PRECIPITATION TYPE WITH HEFTY TOTALS EXPECTED GIVEN THE ANOMALOUS
SLUG OF MOISTURE HITTING THE NEW ENGLAND COAST. IT APPEARS MANY OF
THE MAJOR METROPOLITAN AREAS WILL BE AFFECTED ANYWHERE FROM
PHILADELPHIA THROUGH NEW YORK CITY AND INTO BOSTON. THE WPC WINTER
WEATHER DESK EXPECTS ANYWHERE FROM 18 TO 24 INCHES OF SNOW FROM
SOUTHEASTERN NEW YORK ALL THE WAY ALONG COASTAL NEW ENGLAND. AN
ADDITIONAL MAXIMA IS LIKELY IN THE VICINITY OF EASTERN
MASSACHUSETTS WHERE 24 TO 30 INCHES OF SNOW IS POSSIBLE. GIVEN THE
MESOSCALE NATURE OF HEAVY SNOW BANDS, ISOLATED AREAS OF EVEN
HIGHER AMOUNTS CANNOT BE RULED OUT.

AS THE SURFACE LOW DEEPENS RATHER MARKEDLY LATE MONDAY NIGHT, THE
PRESSURE GRADIENT WILL INCREASE RESULTING IN VERY WINDY CONDITIONS
ACROSS THE NORTHEASTERN STATES. IN PARTICULAR, FORECAST WIND GUSTS
MAY EASILY REACH THE 40 TO 70 MILE PER HOUR RANGE RESULTING IN
NEAR-ZERO VISIBILITY GIVEN THE ABUNDANCE OF SNOW ON THE GROUND.
THIS HAS RESULTED IN BLIZZARD WARNINGS BEING ISSUED FROM
SOUTHEASTERN NEW YORK/NORTHEASTERN NEW JERSEY UP THE COASTLINE TO
NORTHEASTERN MAINE.

VERY WARM TEMPERATURES FOR LATE JANUARY TO PREVAIL OVER THE
CENTRAL U.S. PERSISTENT DOWNSLOPING FLOW IN THE LEE OF THE ROCKIES
WILL PROMOTE AMPLE WARMTH OVER THE NORTHERN ROCKIES AND INTO MUCH
OF THE GREAT PLAINS. TEMPERATURES ANOMALIES ARE EXPECTED TO PEAK
AROUND THE 25 TO 30 DEGREE ABOVE NORMAL RANGE. THIS WOULD SUGGEST
HIGHS INTO THE LOW 70S OVER THE CENTRAL PLAINS EARLY THIS WEEK.

ELSEWHERE, A SECONDARY CLIPPER SYSTEM WILL AFFECT THE UPPER GREAT
LAKES ON MONDAY WITH ONLY A FEW INCHES OF SNOW EXPECTED GIVEN THE
WEAK NATURE OF THE FEATURE. OUT WEST, AN UPPER LOW INITIALLY
ANCHORING THE SUBTROPICAL EAST PACIFIC WILL LIFT NORTHWARD
SPREADING A BROAD AXIS OF LIGHT TO MODERATE RAINFALL. SNOW LEVELS
WILL BE RATHER HIGH KEEPING WINTRY PRECIPITATION CONFINED TO THE
HIGHER ELEVATIONS OF THE CENTRAL SIERRA NEVADA RANGE.


RUBIN-OSTER


GRAPHICS AVAILABLE AT WWW.WPC.NCEP.NOAA.GOV
$$




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