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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 090259
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
959 PM EST SUN DEC 8 2013

.SYNOPSIS...
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LOW PRESSURE EAST OF CAPE HATTERAS THIS EVENING WILL MOVE NORTH TO
A POSITION OFF THE SOUTHERN NEW JERSEY COAST OVERNIGHT...THEN
PASS SLOWLY SOUTHEAST OF LONG ISLAND ON MONDAY. THE LOW WILL THEN
MOVE INTO THE CANADIAN MARITIMES MONDAY NIGHT...WITH HIGH PRESSURE
BUILDING IN FROM THE WEST LATE. ANOTHER WEAK LOW WILL PASS TO
THE SOUTH ON TUESDAY...FOLLOWED BY A SERIES OF COLD FRONTAL
PASSAGES DURING THE MID TO LATE WEEK...AND ANOTHER WEAK LOW
PASSING TO THE SOUTH THIS WEEKEND.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
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EARLIER WIDESPREAD SNOW OVER NYC METRO AND LONG ISLAND HAS MOVED
OFF TO THE EAST...LEAVING LIGHT FREEZING DRIZZLE/SNIZZLE IN ITS
WAKE DUE TO LOSS OF MID LEVEL MOISTURE AND SEEDER-FEEDER ICE
NUCLEATION. COLDER CLOUD TOPS ARE MOVING IN ALOFT...BUT MODEL
SOUNDINGS SHOW TOO MUCH DRY AIR INITIALLY TO RESUME SEEDER-FEEDER
ICE NUCLEATION. THIS SHOULD CHANGE AFTER MIDNIGHT...BUT THEN
WARMER AIR MOVING ALOFT AHEAD OF THE LOW MOVING UP THE COAST
SHOULD RESULT IN LIGHT SNOW/SLEET CHANGING TO FREEZING RAIN FROM
SOUTH TO NORTH OVERNIGHT. CAD FROM OUR AREA UP INTO NEW ENGLAND IS
SLOWLY ERODING...BUT IT AND THE FCST LOW TRACK SHOULD LOCK IN NE
FLOW INLAND AND E-NE FLOW ALONG THE COAST...SO HAVE SLOWED DOWN
OVERNIGHT WARMING TREND PER A BLEND OF EARLIER GFS LAMP AND RAP
TEMPS MINUS A COUPLE OF DEGREES. GOOD POTENTIAL FOR FREEZING RAIN
IN NYC AND LONG ISLAND AFTER MIDNIGHT ESPECIALLY INVOF NYC...AND
THEN POINTS NORTH AND WEST AFTER ABOUT 3 AM.

DO NOT EXPECT SNOWFALL MUCH MORE THAN AN INCH OVERNIGHT AND A
GLAZE OF ICE.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
-- Changed Discussion --
EXTENDED ADVISORIES THROUGH THE MORNING IN MANY AREAS AS COLD AIR
ACROSS INTERIOR SECTIONS WILL BE SLOWER TO ERODE DUE TO NE FLOW
BETWEEN OFFSHORE LOW PRESSURE AND COLD AIR DAMMING STILL IN
PLACE...WITH FREEZING RAIN INLAND AND RAIN ALONG THE COAST.

RAIN LINGERS THROUGH THE AFTERNOON ESPECIALLY EASTERN REGIONS OF
THE AREA WITH TEMPS OVERALL INCREASING INTO THE 40S FOR MUCH OF
THE REGION. FAR INTERIOR PORTIONS OF THE AREA MAY STAY IN THE
UPPER 30S.

RAIN TAPERS OFF AND BECOMES MORE OF SHOWERS IN PRECIP MODE MONDAY
NIGHT. IT WILL BE COLD ENOUGH ACROSS SOME PORTIONS OF THE LOWER
HUDSON VALLEY AND INTERIOR SOUTHWEST CONNECTICUT FOR THESE TO BE
SNOW SHOWERS.

THE UPPER LEVEL JET APPROACHES SLOWLY MONDAY AND MONDAY NIGHT
WHILE PICKING UP IN STRENGTH WITH MAX WINDS INCREASING BACK TO
ABOUT 170-190 KT. 500MB HEIGHTS LOWER THROUGH THE DAY MONDAY AND
MONDAY NIGHT. AT A LARGER SCALE...THE RIDGING ACROSS THE SOUTHEAST
BECOMES FLATTER AS THE WSW TO ENE TROUGH CONTINUES EASTWARD
PROGRESS. TIGHT GRADIENT ALOFT WILL CONVEY A FAST STEERING FLOW.
AT THE SURFACE...THE WEAK LOW MOVES ACROSS THE REGION MONDAY AND
TO THE NORTHEAST OF THE REGION MONDAY NIGHT. HIGH PRESSURE FROM
THE SOUTH AND WEST WILL BUILD IN LATE.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
NO MAJOR CHANGES TO THE FORECAST DURING THIS TIME PERIOD AS THE
POLAR VORTEX OVER HUDSON BAY CONTINUES TO ROTATE A SERIES OF
SHORTWAVES THROUGH THE NORTHERN STATES...USHERING IN SHOTS OF ARCTIC
AIR FOR THE MID TO LATE WEEK.

TUE CONTINUES TO POSE SOME UNCERTAINTY ON WHETHER THE REGION IS
AFFECTED BY A LIGHT SNOW EVENT. THE PLAYERS ARE THE NEXT IN A SERIES
OF NORTHERN STREAM SHORTWAVES AND A BIT OF SOUTHERN STREAM ENERGY
APPROACHING THE REGION TUE...INDUCING A WEAK WAVE OF LOW PRESSURE
ALONG A COLD FRONT STALLED TO THE SOUTH. THE KEY WILL LIE IN THE
AMOUNT OF SOUTHERN STREAM INTERACTION...WHICH ALWAYS POSES SOME
PREDICTABILITY ISSUES. LATEST OPERATIONAL MODELS/ENSEMBLE SOLUTIONS
CONTINUE TO SHOW SPREAD BETWEEN AN ADVISORY LEVEL SNOW EVENT FOR
NYC/LONG ISLAND TO A NEAR MISS...LENDING TO MAINTAINING CHANCE POPS
FOR SOUTHERN ZONES TO SLIGHT CHANCE NORTHERN ZONES. HOWEVER...WITH
THE AREA FALLING UNDER THE RIGHT REAR QUADRANT OF AN UPPER JET
STREAK TO THE NW AND A STRIPE OF H7-5 FRONTOGENESIS PREDICTED JUST
SOUTH OF NYC/LONG ISLAND...THINK NYC/LONG ISLAND/COASTAL SE CT HAVE
A GOOD SHOT AT SEEING SOME LIGHT SNOW...SO BUMPED POP THERE TO
LIKELY...WITH AMTS UP TO AN INCH POSSIBLE.

WILL NOTE THAT THE 18Z GFS/NAM HAVE COME IN SNOWIER...SUGGESTING
A 2-5 INCH SNOWFALL FROM NORTH TO SOUTH. HOWEVER...THE 12Z GEFS
MEAN AND 15Z SREF SHOW ABOUT HALF THAT...SO UNTIL THE ECMWF TRENDS
TOWARD A SNOWIER SOLUTION STILL FEEL IT IS BEST TO PLAY A MIDDLE
GROUND BETWEEN ENSEMBLE MEANS AND THE MAINLY DRY ECMWF...SO NO
FCST CHANGES PLANNED AS OF YET.

THEREAFTER...MODELS CONTINUE TO POINT TO SHOTS OF ARCTIC AIR
BUILDING OVER CANADA AND SPILLING INTO THE NORTHERN STATES.
UNCERTAINTY REMAINS ON HOW MUCH OF THIS AIR MASS SINKS SOUTH AND
TIMING...WHICH WILL BE DEPENDENT ON THE EVOLUTION OF THE HUDSON
BAY POLAR VORTEX THROUGH THE END OF THE WEEK/WEEKEND. THE MID TO
LATE WEEK PD CONTINUES TO LOOK ANOMALOUSLY COLD...WITH HIGHS
STRUGGLING TO GET ABOVE FREEZING FOR MOST OF THE REGION ESPECIALLY
FROM THU ON.

UNCERTAINTY INCREASES IN SENSIBLE WEATHER FOR THIS WEEKEND...WITH
MODEL SPREAD EXISTING IN THE EVOLUTION OF THE POLAR VORTEX. IF ECMWF
EVOLUTION OF THE POLAR VORTEX SINKING INTO SE CANADA IS
CORRECT...TEMPS WOULD BE VERY COLD THIS WEEKEND...STRUGGLING TO
REACH THE UPPER TEENS/LOWER 20S ESPECIALLY ON SAT. FOR NOW
MAINTAINED CONTINUITY WITH PREVIOUS FORECAST OF A SLOW MODERATION IN
TEMPS (STILL 5 TO 10 DEGREES BELOW SEASONABLE) AND POTENTIAL FOR
LIGHT SNOW AS AN ARCTIC COLD FRONT APPROACHES FROM THE NW AND AS
WEAK LOW PRESSURE PASSES OFFSHORE.
-- End Changed Discussion --

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
CHALLENGING FORECAST WITH LOW CONFIDENCE IN DETAILS/TIMING.

LOW PRESSURE CONTINUES TO APPROACH FROM THE SOUTH OVERNIGHT.

LITTLE PRECIP INITIALLY THIS EVENING...BUT DO EXPECT SOME LIGHT
SNOW TO REDEVELOP. AS THE NIGHT PROGRESSES...ANY LIGHT SNOW WILL
BEGIN TO CHANGE OVER TO A MIXTURE OF SNOW/SLEET AND FREEZING RAIN.
AGAIN...AMOUNTS SHOULD BE LIGHT. NEAR THE COAST...A CHANGEOVER TO
PLAIN RAIN IS EXPECTED...WELL AFTER MIDNIGHT. TEMPERATURES SHOULD
RISE ABOVE FREEZING THOUGH BY THE MORNING PUSH FOR NYC METRO AND
COASTAL TERMINALS. INTERIOR AIRPORTS WILL HOLD ON TO FREEZING RAIN
OR DRIZZLE A LITTLE LONGER...INTO THE MORNING AFTER 6 AM.

CEILINGS ARE EXPECTED TO LOWER ONCE AGAIN TO MVFR OR IFR. LIFR
POSSIBLE AFTER MIDNIGHT.

MINOR SNOW ACCUMS POSSIBLE...BUT THE MAIN WEATHER IMPACT WILL BE
LIGHT ICING DUE TO SLEET AND FREEZING RAIN/DRIZZLE.

LOW CLOUDS CONTINUE THROUGH THE DAY MONDAY...REMAINING BELOW 1
KFT...OR IFR/LIFR. SOME IMPROVEMENT TO MVFR LATE IN THE DAY IS
FORECAST.

WINDS OUT OF THE NORTHEAST UNDER 10 KT THROUGH MOST OF THE
NIGHT...THEN AN INCREASE IN WIND OCCURS TOWARD MORNING...MAINLY
FROM THE EAST.

EASTERLY WINDS WILL SHIFT AROUND EARLY AFTERNOON MONDAY...EVENTUALLY
TURNING TOWARD THE WEST AS THE LOW PRESSURE CENTER MOVES EAST LATE
IN THE AFTERNOON.

.OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
.MONDAY NIGHT...CONDITIONS IMPROVING TO VFR. NW WINDS 10-20 KT.
.TUESDAY...MVFR OR LOWER IN -SN.
.TUESDAY NIGHT...IMPROVING CONDITIONS. WEST WINDS 10-20 KT.
.WEDNESDAY...VFR. W-NW WINDS 10-20 KT WITH GUSTS UP TO 25 KT.
.THURSDAY-FRIDAY...VFR.
-- End Changed Discussion --

&&

.MARINE...
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ENOUGH OF A PRESSURE GRADIENT DEVELOPS LATE TONIGHT INTO MONDAY
TO GIVE WIND GUSTS APPROACHING 25-30 KT FOR MOST OF THE
WATERS...OCEAN EARLIER AFTER MIDNIGHT AND INTO VERY EARLY MONDAY
MORNING FOR LONG ISLAND SOUND AND THE BAYS. THIS BECOMES MORE OF A
SEAS ISSUE WITH 5-7 FT SEAS REMAINING ON THE OCEAN MONDAY
AFTERNOON.

SCA CONDS MAY CONTINUE INTO MON NIGHT-TUE ON THE OCEAN ON TUE AS
WEAK LOW PRESSURE PASSES TO THE SOUTH...THEN EXPECT AT LEAST SCA
CONDS ON ALL WATERS TUE NIGHT-WED...WITH POSSIBILITY OF OCEAN
GALES...AS ARCTIC AIR POURS IN BEHIND THE LOW.

MARGINAL SCA CONDS COULD TAKE PLACE AT ANY TIME THEREAFTER THROUGH
FRI NIGHT ON THE OCEAN WATERS...BUT ESPECIALLY THU NIGHT-FRI AFTER
ANOTHER REINFORCING SHOT OF COLD AIR.
-- End Changed Discussion --

&&

.HYDROLOGY...
-- Changed Discussion --
LIQUID EQUIVALENT QPF OF 1/3 TO 1/2 INCH EXPECTED THROUGH MONDAY.
NO HYDROLOGIC ISSUES ANTICIPATED.
-- End Changed Discussion --

&&

.EQUIPMENT...
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD
EMERGENCY BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS
WEATHER RADIO STATION KWO35 REMAINS OUT OF SERVICE. THE NATIONAL
WEATHER SERVICE IS WORKING WITH SEVERAL U.S. GOVERNMENT AGENCIES
TO ISOLATE AND RESOLVE THIS TECHNICAL PROBLEM.

DURING THIS TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TESTS OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR CTZ005>008.
     WINTER WEATHER ADVISORY UNTIL 9 AM EST MONDAY FOR CTZ009>012.
NY...WINTER WEATHER ADVISORY UNTIL 5 AM EST MONDAY FOR NYZ072>075-
     078>081-176>179.
     WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR NYZ067>070.
     WINTER WEATHER ADVISORY UNTIL 9 AM EST MONDAY FOR NYZ071.
NJ...WINTER WEATHER ADVISORY UNTIL 5 AM EST MONDAY FOR NJZ006.
     WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR NJZ002-004-
     103-105.
     WINTER WEATHER ADVISORY UNTIL 9 AM EST MONDAY FOR NJZ104-
     106>108.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO 1 PM EST MONDAY FOR ANZ330-
     335-340-345.
     SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ350-353-355.
-- End Changed Discussion --

&&

$$
SYNOPSIS...GOODMAN/JM
NEAR TERM...GOODMAN
SHORT TERM...JM
LONG TERM...GOODMAN
AVIATION...PW
MARINE...GOODMAN/JM
HYDROLOGY...GOODMAN/JM
EQUIPMENT...