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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 122257
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
557 PM EST THU DEC 12 2013

.SYNOPSIS...
HIGH PRESSURE WILL BUILD EAST INTO THE REGION FOR THE REST OF THE
WEEK. LOW PRESSURE WILL MOVE ACROSS THE OHIO AND TENNESSEE
VALLEYS SATURDAY AND EMERGE OFF THE MID ATLANTIC COAST SATURDAY
NIGHT. THE LOW THEN TRACKS NORTHEAST INTO THE CANADIAN MARITIMES
SUNDAY INTO SUNDAY NIGHT. HIGH PRESSURE BUILDS FOR MONDAY. THEN A
WEAK AND QUICK MOVING FRONTAL SYSTEM AFFECTS THE REGION TUESDAY.
HIGH PRESSURE RETURNS FOR WEDNESDAY AND THURSDAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
-- Changed Discussion --
MINOR UPDATE TO INCREASE CLOUDS ACROSS SERN LI. CANT RULE OUT A
FLURRY THERE. OTHERWISE FCST ON TRACK WITH MINOR TWEAKS TO HOURLY
FIELDS MADE.

ANOTHER QUIET AND COLD NIGHT IN STORE FOR THE REGION AS AN ARCTIC
HIGH PRESSURE BUILDS EAST. THE HIGH WILL REMAIN SLIGHTLY
SUPPRESSED TO THE SOUTH AS A WEAK COLD FRONT DIPS DOWN FROM A LOW
PUSHING THROUGH FAR SOUTHEASTERN CANADA...KEEPING A WESTERLY FLOW
ACROSS THE AREA. FAIRLY DRY AIR MASS REMAINS IN PLACE...SO
EXPECTING ANY PCPN ASSOCIATED WITH THE FRONT TO REMAIN TO OUR
NORTH...THOUGH THE PASSING UPPER LEVEL TROUGH COULD INCREASE CLOUD
COVERAGE OVER INLAND AREAS. THIS COMBINED WITH INCREASED WINDS
WILL KEEP ANY RADIATIONAL COOLING TO A MINIMUM. HOWEVER...WITH
850MB TEMPS STILL AROUND -10 DEGREES...WE SHOULD STILL SEE A VERY
COLD NIGHT...WITH OVERNIGHT LOWS A GOOD 10-15 DEGREES BELOW
NORMAL...AND MOST OF THE REGION SEEING WIND CHILL VALUES IN THE
SINGLE DIGITS.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
SURFACE HIGH BRIEFLY RETREATS TO THE SOUTH AS A WEAK COLD FRONT
PUSHES THROUGH THE NORTHEAST FRIDAY AFTERNOON. THE HIGH BUILDS
BACK UP IN THE WAKE FRIDAY NIGHT...BRINGING ABOUT THE LAST DRIER
WEATHER BEFORE THE APPROACHING LOW PRESSURE SYSTEM FOR THE
WEEKEND. OVERALL...EXPECTING THE PASSAGE OF THE FRONT TO BE DRY
WITH THE PERSISTING ARCTIC AIR MASS KEEPING FAIRLY DRY AIR OVER THE
REGION. THE FRONT ALONG WITH A PASSING WEAK WAVE ALOFT COULD
TRIGGER ISOLATED FLURRIES OVER INTERIOR PORTIONS OF NY AND CT LATE
IN THE DAY AND EARLY FRI EVENING. A PERIOD OF DRY WEATHER THEN
SETS IN BEFORE LIGHT PCPN ASSOCIATED WITH THE APPROACHING LOW
TRACKING THROUGH THE SOUTHEAST BEGINS TO MOVE IN. CURRENTLY JUST
HAVE SLIGHT CHC WITH LIGHT SNOW BY 12Z SAT...DEPENDING ON THE
TIMING OF THE LOW COULD SEE A DIFFERENCE OF PCPN START TIME.
HOWEVER...CONFIDENCE IS THERE THAT ANY INITIAL PCPN WILL BE IN THE
FORM OF LIGHT SNOW.

COLD WEATHER REMAINS THE STORY THROUGH FRIDAY AS 850MB TEMPS
REMAIN AROUND -10 DEGREES. HIGHS FRIDAY WILL BE A COUPLE DEGREES
WARMER...THOUGH STILL AROUND 10 DEGREES BELOW NORMAL. INCREASED
CLOUD COVER AHEAD OF THE APPROACHING SYSTEMS FRI NIGHT WILL KEEP
LOWS IN THE 20S ALONG THE COAST...AND IN THE UPPER TEENS INLAND.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
SOUTHERN STREAM SHORTWAVE MOVING OUT OF THE SOUTHERN PLAINS AND INTO
THE SOUTHEAST WILL DEVELOP A SURFACE LOW MOVING THROUGH THE GULF
COAST STATES. HIGH PRESSURE WILL REMAIN TO THE NORTH OVER
SOUTHEASTERN CANADA AND INTO THE NORTHEAST. COLD ARI DAMNING WILL
KEEP COLD AIR EAST OF THE APPALACHIANS INTO NORTH CAROLINA.
DEVELOPING WARM ADVECTION...AND COASTAL FRONT...ALONG WITH
ISENTROPIC LIFT WILL RESULT IN PRECIPITATION DEVELOPING BY SATURDAY
MORNING. COLD AIR WILL BE IN PLACE AT THE START FOR ALL SNOW. THE
TREND HAS BEEN FOR A WARMER SOLUTION WITH THE EVOLUTION OF THE LOW
AS THE STORM REDEVELOPS OFF THE MID ATLANTIC COAST LATE SATURDAY
INTO SATURDAY EVENING. ALL MODELS ARE TRACKING THE LOW JUST INSIDE
THE BENCHMARK...40/70. FLOW WILL BE PROGRESSIVE AND NO UPPER CLOSED
LOW ASSOCIATED WITH THE SYSTEM. PLENTY OF GULF AND ATLANTIC MOISTURE
WILL BE INCORPORATED INTO THE SYSTEM. MOST OF THE PRECIPITATION WILL
OCCUR AT THE START...SATURDAY INTO THE EVENING. AS WARMER AIR MOVES
INTO A TRANSITION TO RAIN ALONG THE COAST IS LIKELY AND FARTHER
INLAND WILL BE A TRANSITION OF SNOW...SLEET...AND FREEZING
RAIN...TAKING LONGER FOR THE TRANSITION INTO THE LOWER HUDSON VALLEY
UNTIL LATE SATURDAY NIGHT. QPF AMOUNTS VARY WITH THE MODELS AND
LEANED TOWARD THE WPC AND RFC GUIDANCE. SNOWFALL TOTALS WILL BE
LEAST ACROSS SUFFOLK COUNTY NEW YORK WITH THE HIGHEST ACROSS THE
LOWER HUDSON VALLEY...RANGING FROM AROUND 2 INCHES TO 6 INCHES.
PRECIPITATION TYPE AND TIMING TRANSITION WILL HAVE AN IMPACT ON SNOW
AND ICE TOTALS. STILL DO NOT HAVE HIGH ENOUGH CONFIDENCE OF A 6 INCH
SNOWFALL INLAND AND WILL NOT ISSUE ANY WATCHES AT THIS TIME...AND
LOOKS LIKE AN ADVISORY EVENT AT THIS TIME.

THE LOW WILL MOVE AWAY ON SUNDAY...WITH PRECIPITATION ENDING. DRY
WEATHER RETURNS BRIEFLY SUNDAY INTO MONDAY NIGHT. THEN A QUICK
MOVING FRONTAL SYSTEM MOVES THROUGH FOR TUESDAY. HIGH PRESSURE
BUILDS IN FOR TUESDAY NIGHT INTO THURSDAY. FOLLOWED CLOSELY TO THE
CURRENT FORECAST AND WPC GUIDANCE FOR MONDAY NIGHT THROUGH
THURSDAY.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL REMAIN SOUTHWEST OF THE REGION THROUGH TONIGHT.

VFR THROUGH THE TAF PERIOD.

UPDATED WIND DIRECTION FOR THE REST OF TONIGHT...CHANGED FROM WNW
TO WSW FOR ALL TERMINALS FROM NYC NORTH AND WEST.

OTHERWISE...WIND SPEEDS AROUND 10-15 KT WITH GUST POTENTIAL TO AROUND
20KT MAINLY DURING THE EVENING AT COASTAL TERMINALS.

TONIGHT...WINDS REMAIN FROM THE WEST-SOUTHWEST 10-15 KT WITH GUSTS INTO THE
UPPER TEENS AND LOWER 20S AS THE GRADIENT TIGHTENS WITH A PASSING
LOW WELL NORTH OF THE REGION.

     NY METRO ENHANCED AVIATION WEATHER SUPPORT...

DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT:  HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)

KJFK FCSTER COMMENTS: AMENDMENTS NOT ANTICIPATED.

KLGA FCSTER COMMENTS: AMENDMENTS NOT ANTICIPATED.

KEWR FCSTER COMMENTS: AMENDMENTS NOT ANTICIPATED.

KTEB FCSTER COMMENTS: AMENDMENTS NOT ANTICIPATED.

KHPN FCSTER COMMENTS: AMENDMENTS NOT ANTICIPATED.

KISP FCSTER COMMENTS: AMENDMENTS NOT ANTICIPATED.

.OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY...

.FRI...VFR.
.FRI NIGHT...MVFR OR LOWER POSSIBLE LATE.
.SAT-SAT NIGHT...IFR OR LIFR LIKELY. PRECIP TYPE SHOULD BE MOSTLY
SNOW N OF LONG ISLAND SOUND AND INTERIOR NE NJ...AND SNOW MIXING
WITH OR CHANGING TO RAIN AT NIGHT AT THE NYC METRO AND LONG ISLAND
TERMINALS. E WINDS G20-30KT POSSIBLE MAINLY FROM NYC E AT NIGHT.
.SUNDAY...LINGERING SNOW OR RAIN SHOWERS INTO THE AFTERNOON...
BECOMING VFR FROM W TO E DURING THE AFTERNOON.
.SUNDAY NIGHT-MON...VFR.
.TUE...CHANCE OF SUB-VFR IN SNOW SHOWERS

&&

.MARINE...
SCA IN EFFECT FOR ALL WATERS TONIGHT THROUGH FRIDAY WITH A
TIGHTENING PRESSURE GRADIENT WITH THE HIGH TO OUR SOUTH AND AN
APPROACHING COLD FRONT FROM THE NORTH. GUSTS UP TO 30 KTS WILL BE
PSBL...ESP FRIDAY MORNING...WITH SEAS ON THE OCEAN REACHING 4-6 FT
FRIDAY. CONDITIONS WILL START TO DIMINISH LATE FRIDAY FROM WEST TO
EAST AS THE HIGH BUILDS IN BEHIND THE DEPARTING FRONT.

LOW PRESSURE OVER THE OHIO AND TENNESSEE VALLEYS WILL MOVE OFF THE
MID ATLANTIC COAST SATURDAY NIGHT...PASSING SOUTH AND EAST OF THE
FORECAST WATERS THROUGH SUNDAY AS THE LOW HEADS INTO THE CANADIAN
MARITIME. SMALL CRAFT CONDITIONS ARE LIKELY ACROSS THE FORECAST
WATERS SATURDAY NIGHT INTO SUNDAY NIGHT IN ASSOCIATION WITH THE
LOW. BEHIND THE LOW LATE SUNDAY INTO SUNDAY NIGHT THERE IS A
POTENTIAL FOR A BRIEF PERIOD OF GALE FORCE GUSTS ON THE OCEAN
WATERS. SEAS WILL BE SLOW TO SUBSIDE WITH SMALL CRAFT SEAS ON THE
OCEAN WATERS LINGERING INTO TUESDAY NIGHT.

&&

.HYDROLOGY...
SIGNIFICANT PRECIPITATION IS LIKELY SATURDAY INTO SUNDAY IN
ASSOCIATION WITH A COASTAL LOW. LIQUID EQUIVALENT QPF RANGES FROM
3/4 TO 1 INCH...FALLING MAINLY AS SNOW ACROSS NORTHERN NEW JERSEY
INTO THE LOWER HUDSON VALLEY AND ACROSS SOUTHERN CONNECTICUT.
DRY WEATHER RETURNS SUNDAY NIGHT INTO THE BEGINNING OF NEXT WEEK.

&&

.EQUIPMENT...
THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 HAS
BEEN RETURNED TO SERVICE. HOWEVER...IF ISSUES ARISE AGAIN DUE TO
INTERFERENCE WITH THE U.S. COAST GUARD EMERGENCY BROADCAST
CHANNEL...THE TRANSMITTER MAY NEED TO BE TAKEN OUT OF SERVICE. IF THIS
DOES OCCUR...A NOTICE WILL BE MADE TO THE PUBLIC NOTIFYING THEM OF
SUCH.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ338-355.
     SMALL CRAFT ADVISORY FROM 1 AM TO 6 PM EST FRIDAY FOR ANZ330-
     335.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 1 AM EST
     SATURDAY FOR ANZ350-353.
     SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 6 PM EST
     FRIDAY FOR ANZ340-345.

&&

$$
SYNOPSIS...SEARS/MET
NEAR TERM...JMC/SEARS
SHORT TERM...SEARS
LONG TERM...MET
AVIATION...BC/GC
MARINE...SEARS/MET
HYDROLOGY...MET
EQUIPMENT...