-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 121458
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
958 AM EST THU DEC 12 2013

.SYNOPSIS...
ARCTIC HIGH PRESSURE WILL BUILD EAST INTO THE AREA FOR THE REST
OF THE WEEK. LOW PRESSURE WILL MOVE ACROSS THE OHIO AND TENNESSEE
VALLEYS ON SATURDAY... EMERGE OFF THE MID ATLANTIC COAST SATURDAY
NIGHT...THEN HEAD NORTHEAST INTO THE CANADIAN MARITIMES ON SUNDAY.
CANADIAN HIGH PRESSURE WILL THEN BUILD IN THROUGH MONDAY. A WEAK
FRONTAL SYSTEM WILL MOVE ACROSS ON TUESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
FORECAST REMAINS ON TRACK FOR THE DAY.

STRONG HIGH PRES CENTERED OVER THE MIDWEST WILL BUILD EAST INTO
THE REGION TODAY BEHIND A DEPARTING COLD FRONT.

850 MB TEMPS WILL DROP DOWN TO -18C...YIELDING SFC TEMPS ABOUT 15
DEGREES BELOW NORMAL TODAY. HIGHS WILL TOP OFF IN THE MID TO UPPER
20S...STRUGGLING TO REACH 30.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
COLD HIGH PRES OVER THE MIDWEST CONTINUES TO BUILD EAST TONIGHT
THROUGH FRIDAY. MEANWHILE...LOW PRES WILL TRACK ACROSS SOUTHERN
CANADA...BUT SHOULD STAY WELL NORTH OF THE REGION. WILL KEEP THE
FORECAST DRY...AS ANY SNOW SHOWERS ASSOCIATED WITH THE LOW WILL STAY
TO THE NORTH. LOWS TONIGHT DROP INTO THE LOWER TEENS ACROSS THE
INTERIOR AND WILL TOP OFF IN THE MID TO UPPER TEENS ELSEWHERE. WIND
CHILL VALUES WILL BE IN THE SINGLE DIGITS.

HIGH PRES MOVES OFF THE MID-ATLANTIC COAST ON FRIDAY...AND TEMPS
MODERATE SOMEWHAT...BUT WILL STILL BE ABOUT 10 DEGREES BELOW
NORMAL...TOPPING OFF IN THE UPPER 20S TO LOWER 30S. WIND CHILL
VALUES WILL BE IN THE TEENS AND LOWER 20S.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
ALL EYES TURN TO LOW PRESSURE MOVING FROM THE SOUTHERN PLAINS TO
THE OH/TN VALLEYS FROM FRI NIGHT INTO SAT...THEN REDEVELOPING
ALONG THE NC COAST SAT NIGHT AND HEADING NE ACROSS THE 40N/70W
BENCHMARK SUNDAY MORNING. GFS/ECMWF ARE GOOD AGREEMENT ON THE LOW
TRACK AND INTENSITY...AND ON THE STRENGTH AND POSITION OF AN
ARCTIC HIGH TO THE NE THAT WILL PROVIDE A LOW LEVEL FEED OF COLD
AIR. LIGHT OVERRUNNING SNOWS SHOULD DEVELOP DURING THE DAY ON SAT
AS MOISTURE OVERRUNS THE NEARBY ARCTIC FRONT...THEN THE HEAVIEST
PRECIP SHOULD OCCUR SAT NIGHT VIA STRONGER ISENTROPIC LIFT AND
H7-8 FRONTOGENESIS AHEAD OF THE APPROACHING LOW. AS FAR AS THERMAL
PROFILES GO...BOTH MODELS ARE LIKELY TOO WARM IN THE BOUNDARY
LAYER...ESPECIALLY INLAND WHERE COLD AIR DAMMING SHOULD HANG IN
LONGER THAN MODEL FCST...AND EVEN AT THE COAST WHERE SNOWFALL
SHOULD COUNTERACT WARMING ON EASTERLY FLOW. THEY ALSO DISAGREE ON
THERMAL PROFILES ALOFT ESPECIALLY LATE SAT NIGHT...WITH THE ECMWF
COLD ENOUGH FOR AN ALL SNOW EVENT NW OF NYC...AND SNOW MIXING WITH
OR CHANGING TO RAIN FOR NYC AND LONG ISLAND...AND THE GFS SHOWING
A CHANGE TO FREEZING RAIN AND SLEET INLAND LATE SAT NIGHT. SINCE
THE BETTER PART OF THE PRECIP WILL HAVE FALLEN BY THE TIME P-TYPE
BEGINS TO CHANGE FROM SNOW...THESE DIFFERENCES SHOULD NOT HAVE A
MAJOR IMPACT ON SNOWFALL AMOUNTS...SO THINK MOST INLAND SECTIONS
AND ALL OF SOUTHERN CT SHOULD SEE SNOWFALL AMOUNTS OF 5-7
INCHES...WITH NYC AND LONG ISLAND SEEING AMOUNTS OF 2-4 OR 3-5
INCHES. CONFIDENCE IS INCREASING ON THESE AMOUNTS...AND A WINTER
STORM WATCH MAY EVENTUALLY BE ISSUED FOR MOST AREAS NW OF NYC AND
SOUTHERN CT.

THE LOW WILL MOVE AWAY ON SUNDAY...WITH LEFTOVER LIGHT PRECIP
TAPERING OFF GRADUALLY DURING THE DAY.

BEHIND THIS LOW...MOSTLY DRY CONDITIONS ARE EXPECTED WITH HIGH
PRESSURE OVER THE REGION. THE ONLY EXCEPTION WILL BE ON TUE-TUE
NIGHT...AS A SHORTWAVE AND ASSOCIATED WEAK FRONTAL SYSTEM MOVE ACROSS
WITH POSSIBLE SNOW AND RAIN SHOWERS. TEMPS SHOULD MODERATE LATER
THIS WEEK AFTER THIS FRONTAL PASSAGE BUT WILL STILL BE BELOW AVG.

&&

.AVIATION /15Z THURSDAY THROUGH MONDAY/...
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HIGH PRESSURE BUILDING INTO OUR SOUTHWEST THROUGH TONIGHT.

VFR THROUGH THE TAF PERIOD.

NW WINDS WILL BACK TO WNW BY MID-LATE AFTERNOON WITH A SLIGHT
DECREASE IN SPEED. COULD SEE SOME OCCASIONAL GUSTS TO AROUND 20
KT THROUGH MID MORNING. WINDS CONTINUE TO BACK TO THE W BY EARLY
EVENING WITH SPEEDS AROUND 10-15 KT COULD SEE SOME GUSTS TO AROUND
20KT MAINLY DURING THE EVENING AT COASTAL TERMINALS.

     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: TIMING OF WIND DIRECTION CHANGES AND OF GUSTS
COULD BE OFF +/- 2 HOURS. WINDS MAINLY TO THE RIGHT OF 300
TRUE/310 MAGNETIC UNTIL EARLY AFTERNOON...THOUGH COULD
OCCASIONALLY TOUCH.

KLGA FCSTER COMMENTS: TIMING OF WIND DIRECTION CHANGES AND OF GUSTS
COULD BE OFF +/- 2 HOURS. WINDS MAINLY TO THE RIGHT OF 300
TRUE/310 MAGNETIC UNTIL EARLY AFTERNOON...THOUGH COULD
OCCASIONALLY TOUCH OR GO TO 290.

KEWR FCSTER COMMENTS: TIMING OF WIND DIRECTION CHANGES AND OF GUSTS
COULD BE OFF +/- 2 HOURS. WINDS MAINLY TO THE RIGHT OF 300
TRUE/310 MAGNETIC UNTIL EARLY AFTERNOON...THOUGH COULD
OCCASIONALLY TOUCH.

THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH
IMPLIES  SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.

KTEB FCSTER COMMENTS: TIMING OF WIND DIRECTION CHANGES AND OF GUSTS
COULD BE OFF +/- 2 HOURS.

KHPN FCSTER COMMENTS: TIMING OF WIND DIRECTION CHANGES AND OF GUSTS
COULD BE OFF +/- 2 HOURS.

KISP FCSTER COMMENTS: TIMING OF WIND DIRECTION CHANGES AND OF GUSTS
COULD BE OFF +/- 2 HOURS.

.OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...

.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.
-- End Changed Discussion --

&&

.MARINE...
SCA CONTINUES FOR THE OCEAN WATERS INTO LATE MORNING OR EARLY
AFTERNOON...WITH MAX SEAS NEAR 5 FT AND WINDS GUSTING 25-30 KT.

PRES GRADIENT TIGHTENS BACK UP TONIGHT...AND WINDS/SEAS BUILD
BACK UP TO SCA CRITERIA FOR TONIGHT THROUGH FRIDAY.

SCA CONDITIONS WILL DEVELOP ON SAT AS NE-E WINDS INCREASE AHEAD OF
A COASTAL LOW. GALES ARE POSSIBLE ON THE OCEAN JUST AHEAD OF THE
LOW SAT NIGHT. POST-FRONTAL NW FLOW SHOULD ALSO BRING SCA
CONDITIONS MAINLY TO THE OCEAN AND ERN SOUND/BAYS SUNDAY INTO MON.

&&

.HYDROLOGY...
SIGNIFICANT PRECIP IS LIKELY THIS WEEKEND IN ASSOCIATION WITH A
COASTAL LOW PRES SYSTEM. LIQUID EQUIVALENT QPF RANGES FROM 1/2 TO
3/4 INCH...FALLING MOSTLY AS SNOW.

&&

.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...
-- Changed Discussion --
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR ANZ353-
     355.
     SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR ANZ350.
-- End Changed Discussion --

&&

$$
SYNOPSIS...GOODMAN/MPS
NEAR TERM...GOODMAN/MPS
SHORT TERM...MPS
LONG TERM...GOODMAN
AVIATION...BC/MALOIT
MARINE...GOODMAN/MPS
HYDROLOGY...GOODMAN/MPS
EQUIPMENT...