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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 172331
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
731 PM EDT MON JUN 17 2013

.SYNOPSIS...
A COLD FRONT MOVING INTO THE REGION BECOMES NEARLY STATIONARY
ACROSS THE AREA INTO TUESDAY. THE COLD FRONT PUSHES SOUTHEAST OF
THE REGION TUESDAY NIGHT...WITH A WEAK WAVE OF LOW PRESSURE
PASSING SOUTH ON WEDNESDAY. HIGH PRESSURE BUILDS OVER THE AREA FOR
THE MIDDLE TO THE END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
SEVERE THUNDERSTORM WATCH 321 IN EFFECT UNTIL 9PM FOR MOST OF
SOUTHERN CONNECTICUT.

WITH THE BULK OF THE THUNDERSTORMS FOCUSED ON SOUTHERN CT...WILL
GO AHEAD AND CANCEL THE SEVERE THUNDERSTORM WATCH UP FOR THE LOWER
HUDSON VALLEY AND SOUTHWEST CT. ONCE THROUGH CT...MOST OF THE
STORMS HAVE ENCOUNTERED THE MARINE LAYER...WHICH HAS LED TO STORMS
DIMINISHING IN INTENSITY. MAIN THREAT FROM STORMS WILL BE FROM
DAMAGING WINDS.

AFTER 03 UTC...MOST OF THE SHOWERS/STORM ACTIVITY WILL DISSIPATE
WITH LOSS OF DAYTIME HEATING/INSTABILITY. PARTLY TO MOSTLY CLOUDY
SKY CONDITIONS EXPECTED FOR THE REMAINDER OF THE NIGHT. THE
CONVECTION MAY BRING A WIND SHIFT WITH NW WINDS...BUT SOME
UNCERTAINTY IN HOW FAR SOUTH THIS BOUNDARY MOVES. FOR LOW
TEMPERATURES...A MAV/MET BLEND USED WHICH YIELDS READINGS IN THE
UPPER 50S AND LOWER 60S EXCEPT HIGHER IN NEW YORK CITY.

THERE IS A MODERATE RISK OF RIP CURRENTS INTO THIS EVENING.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/...
NORTHERN STREAM TROUGH AXIS MOVES INTO THE REGION ON TUESDAY. THIS
COUPLED WITH A STALLED BOUNDARY IN THE AREA WILL PRODUCE MORE
SHOWERS AND THUNDERSTORMS...ESPECIALLY DURING THE AFTERNOON AND
EARLY EVENING.

THERE ARE STILL SOME DISCREPANCIES WITH THE LATEST MODEL OUTPUT
AND IT APPEARS MUCH OF THIS HINGES ON WHERE EXACTLY BOUNDARY
STALLS. FOR NEW YORK CITY AND INTERIOR SECTIONS...FORECAST MODELS
DO INDICATE BETWEEN 1000 TO 2000 J/KG OF CAPE. AT THE
COAST...BETWEEN 500 AND 1000 J/KG OF CAPE FORECAST. THE NAM IS
SLIGHTLY HIGHER ACROSS THE REGION. THE REGION WILL ALSO BE NEAR
THE LEFT EXIT REGION OF A 100+ KT 250 HPA JET...AND HAVE 40-50 KT
OF 0-6 KM BULK SHEAR. IF WE DO REALIZE THE HIGHER INSTABILITY...HAVE
THE POTENTIAL FOR A FEW STRONG TO SEVERE STORMS WITH THE MAIN
THREAT BEING DAMAGING WINDS. HAVE CAPPED POPS AT 50 PERCENT AT
THIS TIME.

FOR HIGHS TUESDAY...GENERALLY USED A MAV/MET BLEND WITH MORE
WEIGHT ON THE MAVS. THIS YIELDS HIGHS IN THE UPPER 70S AND LOWER
80S...WARMEST IN NE NJ AND NYC.

STILL COULD SEE A FEW SHOWERS AND STORMS BEFORE MIDNIGHT WITH MOST
OF THE ACTIVITY SHIFTING SOUTH OF THE REGION AFTER MIDNIGHT AS
THE MAIN COLD FRONT SHIFTS SOUTH. THE UPPER LEVEL TROUGH AXIS ALSO
WILL BE SHIFTING SOUTH AND EAST AND TAKING THE BEST FORCING
WITH IT.

LOWS TUESDAY NIGHT IN THE UPPER 50S AND LOWER 60S WITH A MOSTLY
CLOUDY SKY CONDITION.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
ANY SHOWERS TAPER OFF EARLY WEDNESDAY MORNING AS HIGH PRES BUILDS
INTO THE REGION BEHIND THE DEPARTING COLD FRONT. THIS HIGH WILL THEN
DOMINATE THE WEATHER PATTERN FOR THE REST OF THE WEEK...WITH MAINLY
DRY CONDS WITH SEASONAL TEMPERATURES THROUGH FRIDAY.

THE HIGH MOVES OFFSHORE LATE FRIDAY...AND THEN A WARM FRONT WILL
LIFT NORTH THROUGH THE REGION BEHIND THE HIGH. THIS WILL BRING
WARMER AND MORE UNSETTLED WEATHER TO THE REGION WITH TEMPS WARMING
INTO THE 80S.

MCS ACTIVITY OVER THE MIDWEST BECOMES MORE LIKELY STARTING THIS
WEEKEND. THE REMNANTS OF THOSE SYSTEMS WILL WEAKEN AS THEY TRACK
EAST...BUT THERE MAY BE ENOUGH UPPER LEVEL ENERGY AND SFC
INSTABILITY FOR ISO-SCT AFTERNOON/EVENING TSTMS...MAINLY OVER
WESTERN PORTIONS OF THE CWA.

THE BEST CHANCES FOR WIDESPREAD SHRA/TSRA ACTIVITY WILL BE LATE
SUNDAY AND SUNDAY NIGHT AS LOW PRES DEVELOPS ALONG A WARM FRONT
LIFTING NORTH THROUGH THE REGION.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
A COLD FRONT WILL SLOWLY MOVE ACROSS THE AREA TONIGHT AND REMAIN IN
THE VICINITY TUESDAY.

GENERALLY VFR TONIGHT...EXCEPT PERHAPS MVFR VSBYS IN FOG OVERNIGHT.
ANY LINGERING SHOWERS/TSTMS WILL DIMINISH THIS EVENING.

FOR TUESDAY...ANY LINGERING MVFR VSBYS IN FOG OR HAZE WILL IMPROVE
TO 6SM OR BETTER BY AFTERNOON. ADDITIONAL CONVECTION IS POSSIBLE
TUESDAY AFTERNOON...BUT ACTIVITY IS EXPECTED TO BE SCATTERED. NO
MENTION IN ANY INDIVIDUAL TAF AT THIS TIME DUE TO EXPECTED
COVERAGE...BUT SHOWERS/TSTMS ARE POSSIBLE IN THE AFTERNOON.

WINDS LIGHTEN OVERNIGHT AND SHOULD BECOME VARIABLE MOST IF NOT ALL
TERMINALS. WINDS REMAIN LIGHT FROM THE EAST IN THE MORNING
TUESDAY...THEN SE DURING THE AFTERNOON. SPEEDS SHOULD REMAIN BELOW
10 KTS...OUTSIDE ANY THUNDERSTORMS.

     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: VFR THIS EVENING WITH LIGHT WINDS. AN
AFTERNOON SHOWER OR THUNDERSTORM IS POSSIBLE TUESDAY AFTERNOON.

KLGA FCSTER COMMENTS: VFR THIS EVENING WITH LIGHT WINDS. NE WINDS
EXPECTED OFF THE LONG ISLAND SOUND TUESDAY MORNING. AN AFTERNOON
SHOWER OR THUNDERSTORM IS POSSIBLE TUESDAY AFTERNOON.

KEWR FCSTER COMMENTS: VFR THIS EVENING WITH LIGHT WINDS. AN
AFTERNOON SHOWER OR THUNDERSTORM IS POSSIBLE TUESDAY AFTERNOON.

KTEB FCSTER COMMENTS: MAINLY VFR THIS EVENING...BUT POSSIBLE FOG
DEVELOPMENT LATER THIS EVENING AND OVERNIGHT. AN AFTERNOON SHOWER OR
THUNDERSTORM IS POSSIBLE TUESDAY AFTERNOON.

KHPN FCSTER COMMENTS: MAINLY VFR THIS EVENING...BUT POSSIBLE FOG
DEVELOPMENT LATER THIS EVENING AND OVERNIGHT. AN AFTERNOON SHOWER OR
THUNDERSTORM IS POSSIBLE TUESDAY AFTERNOON.

KISP FCSTER COMMENTS: MAINLY VFR THIS EVENING...BUT POSSIBLE FOG
DEVELOPMENT LATER THIS EVENING AND OVERNIGHT. AN AFTERNOON SHOWER OR
THUNDERSTORM IS POSSIBLE TUESDAY AFTERNOON.

.OUTLOOK FOR 00Z WED THROUGH SAT...
.TUE NIGHT...SUB VFR POSSIBLE IN LINGERING SHOWERS/TSTMS AND FOG.
.WED-SAT...VFR.
-- End Changed Discussion --

&&

.MARINE...
THUNDERSTORMS WILL MAINLY IMPACT LI SOUND THROUGH THIS EVENING AS
THEY TRACK SOUTH THROUGH CT. STORMS WILL BE CAPABLE OF WINDS
GREATER THAN 40 KT...HEAVY RAIN...AND DANGEROUS LIGHTNING. BY
03Z...WITH LOSS OF DIURNAL HEATING...STORMS WILL WIND DOWN.

OTHERWISE...WITH A RELATIVELY LIGHT PRESSURE GRADIENT OVER THE
REGION EXPECT WINDS TO GENERALLY BE 15 KT OR LESS THROUGH
TUESDAY...OUTSIDE OF AFTERNOON SEABREEZES EACH DAY AND ANY
THUNDERSTORMS. WAVES SHOULD REMAIN BELOW SCA LEVELS ON THE OCEAN
WATERS THROUGH TUESDAY NIGHT.

HIGH PRES BUILDS OVER THE WATERS STARTING ON WEDNESDAY AND MOVES
OFFSHORE ON SATURDAY. WINDS/WAVES WILL REMAIN BELOW SCA CRITERIA
THROUGH THE PERIOD.

&&

.HYDROLOGY...
BASIN AVERAGE QPF FROM ANY SHRA/TSTMS THIS AFTERNOON/EARLY EVENING
SHOULD BE LESS THAN .1 INCHES. THE PROBABILITY OF LOCALLY HEAVY
RAINFALL...AND HENCE ANY SIGNIFICANT HYDROLOGIC IMPACT IS LOW.

THERE IS THE POTENTIAL FOR 1/3-2/3 AN INCH OF BASIN AVERAGE
QPF...WITH LOCALLY HIGHER AMOUNTS POSSIBLE WITH CONVECTION
TUESDAY/TUESDAY EVENING. WITH PRECIPITABLE WATERS OF 1.25-1.5
INCHES...THERE IS THE POTENTIAL FOR LOCALLY HEAVY RAINFALL WITH
ANY STRONGER CONVECTION. THIS COULD CAUSE MINOR FLOODING OF
URBAN/POOR DRAINAGE AREAS.

THE PROBABILITY FOR WIDESPREAD SIGNIFICANT RAINFALL IS LOW FROM
THE MIDDLE THROUGH THE END OF THE WEEK.

FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...MPS/DS
NEAR TERM...MPS/DS
SHORT TERM...DS
LONG TERM...MPS
AVIATION...PW
MARINE...MPS/DS
HYDROLOGY...MPS/DS