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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 210139
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
939 PM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM FRONT NORTH OF THE AREA WILL SINK SOUTH CLOSER TO THE AREA
ON TUESDAY...THEN LIFT BACK NORTH AS A WARM FRONT ON WEDNESDAY.
A WARM AND HUMID AIR MASS WILL REMAIN OVER THE AREA UNTIL A COLD
FRONT MOVES THROUGH THURSDAY NIGHT. HIGH PRESSURE WILL RETURN FOR
THE WEEKEND AND EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
-- Changed Discussion --
BROKEN TO SCATTERED STRATUS REMAINS OVER LONG ISLAND FROM NEAR
ISLIP AND EAST. FOG BANK SOUTH OF LONG ISLAND STILL EXPECTED TO
EXPAND NORTHWARD TONIGHT. CONTINUE WITH THE DENSE FOG ADVY
BEGINNING AT MIDNIGHT FOR SAME AREAS AS LAST NIGHT. DEW POINTS
REMAIN IN THE LOWER 60S AND WITH ONSHORE FLOW TEMPERATURE REMAIN
IN THE MID 60S.

LOWS SHOULD BE TIED CLOSELY TO JUICY MID AFTN DEW POINTS IN MOST
PLACES...MOSTLY LOWER AND MID 60S...EXCEPT MID/UPPER 60S IN NYC.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
FRONTAL BOUNDARY WILL REMAIN TO THE NORTH ON TUE AS RIDGE PREVAILS
ACROSS THE NORTHEAST AHEAD OF UPSTREAM TROUGH...THEN DROP S INTO
SOUTHERN CT AND PERHAPS ERN LONG ISLAND TUE NIGHT. THE FRONT
SHOULD BE PRECEDED BY DIURNAL CONVECTION MAINLY INLAND LATE TUE
AFTERNOON AND EARLY EVENING...THEN A GENERAL CHANCE FOR SHOWERS
AND ISOLD THUNDER LATER TUE NIGHT.

TUE SHOULD FEATURE MORE SUNSHINE THAN TODAY AFTER MORNING FOG
BURNS OFF...AND WITH ARE MORE FIRMLY ENTRENCHED IN THE WARM SECTOR
EXPECT HIGHS IN THE 80S INLAND AND ALONG THE NORTH SHORE OF WRN
LONG ISLAND...AND 70S IN COASTAL CT AND THE REST OF LONG ISLAND.

LOW CLOUDS AND FOG SHOULD REDEVELOP TUE NIGHT...MAINLY LATER AT
NIGHT AS IT WILL TAKE BLYR LONGER TO COOL DOWN CLOSER TO
DEW POINTS.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
MODELS COMING INTO BETTER AGREEMENT ABOUT THE MAIN FEATURES OF THE
WEEK. LONG TERM STARTS OUT WITH UPPER RIDING OVER THE AREA WITH
A MIDWEST TROUGH BEGINNING TO PHASE WITH A CANADIAN TROUGH. A WARM
FRONT WILL BE TO THE NORTH OF THE AREA BY WEDNESDAY...EXTENDING FROM
A LOW PRESSURE AREA OVER THE MIDWEST.

A WARM SOUTHERLY FLOW SETS UP BEHIND THE WARM FRONT...ALLOWING TEMPS
ON WEDNESDAY TO WARM TO ABOVE NORMAL VALUES. THERE IS A WIDE RANGE
OF HIGH TEMP VALUES ON WED...NAM 2M TEMPS HAS HIGHS IN THE LOWER 90S
OUT WEST...WHICH COULD POSSIBLY BE DUE TO DIFFERENCES IN CLOUD
COVER. HAVE LEANED TOWARD THE WARMER MET...NOT AS WARM AS THE
NAM...WITH HIGHS IN THE MIDDLE 70S TO MIDDLE TO UPPER 80S. LOWS
WILL BE SLIGHTLY ABOVE NORMAL.

ALSO ON WEDNESDAY...WITH THE MOIST SOUTHERLY FLOW NEAR THE WARM
FRONTAL BOUNDARY...THUNDERSTORMS ARE POSSIBLE. ML AND SFC CAPE WEST
OF NYC WILL BE REACHING ABOVE 1000 J/KG IN THE AFTERNOON ALONG WITH
DECENT LOW LEVEL LAPSE RATES. EVEN WITH THE FRONT NEARBY...LIFT MAY
NOT BE STRONG ENOUGH TO GENERATE ANY WIDESPREAD THUNDERSTORMS. ANY
THUNDERSTORMS THAT DO DEVELOP MAY PRODUCE HEAVY RAIN WITH PW ABOVE
1.5 INCHES. ONLY HAVE CHANCE POPS IN WED AS THERE IS SOME
DISCREPANCY ON THE TIMING OF THE PRECIP APPROACHING THE AREA AND THE
COVERAGE OF IT.

DEEP TROUGH THEN DEVELOPS OVER THE MIDWEST ON THURSDAY AND TRACKS
EAST WITH THE ASSOCIATED LOW PRESSURE TRACKING NE INTO CANADA AND
DRAGGING A COLD FRONT SOUTH OF IT. COLD FRONT APPROACHES THURSDAY
EVENING WITH A PRE FRONTAL TROUGH DEVELOPING AHEAD OF IT...ONCE
AGAIN TRIGGERING SCT SHOWERS AND THUNDERSTORMS. INSTABILITY WILL BE
SLIGHTLY LESS THAT WED BUT BETTER LIFT WILL BE EVIDENT. STILL NOT
EXPECTING ANYTHING SEVERE BUT MAY SEE STRONG STORMS THAT WED. DO
HAVE LIKELY POPS IN FOR THURSDAY AFTERNOON AND EVENING AS MODELS ARE
IN GOOD AGREEMENT OF THE TIMING OF THE RAINFALL. TEMPS WILL BE
COOLER THAN WEDNESDAY...A FEW DEGREES ABOVE NORMAL.

THE TROUGH MOVES EAST AND RAIN ENDS WEST TO EAST BY FRIDAY AFTERNOON
WITH HIGH PRESSURE BUILDING IN ITS WAKE AND WINDS SHIFTING TO THE
NORTHWEST. MEMORIAL DAY WEEKEND WILL BE DRY WITH TEMPS RIGHT AT
NORMAL. HIGHS WILL WILL BE IN THE UPPER 60S TO LOWER 70S FRI-MON.
LOWS WILL BE IN THE MIDDLE 40S TO LOWER 50S.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
WARM...MOIST AIR WILL OVERSPREAD THE REGION TONIGHT...RESULTING IN
WIDESPREAD FOG/STRATUS THROUGH TUESDAY MORNING.

CONDS DIMINISHING TO IFR/LIFR AS THE EVENING PROGRESSES. FOG BANK
CURRENTLY SOUTH OF LONG ISLAND CONTINUING TO TRACK EAST...BUT WITH
VERY WARM AND HUMID AIR PUSHING NORTH FROM OFF THE OCEAN...WILL
EXPECT FOG TO REDEVELOP BY 04Z.

CONDS GRADUALLY IMPROVE TO VFR BY MIDDAY TUESDAY.

 ...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)

KEWR FCSTER COMMENTS: CONDS GRADUALLY LOWERING TO IFR BY 04Z. VFR
EXPECTED TO RETURN BY 15Z TUESDAY. SW WINDS AROUND 230 DEGREES
TRUE AT 10 KT OR LESS THROUGH AROUND 15Z TUESDAY.

KJFK FCSTER COMMENTS: MONITORING FOG DEVELOPMENT THIS
EVENING...WITH IFR CONDS BY 04Z...AND AS LOW AS VLIFR BY 09Z.
CONDS IMPROVE TO VFR 15-16Z TUESDAY. LIGHT S WINDS...TURNING SW
LATE.

KLGA FCSTER COMMENTS: IFR CONDS DEVELOPING BY 04Z WITH IMPROVEMENT
AFT 15Z. SW WINDS 5-7 KT.

KTEB FCSTER COMMENTS: IFR CONDS DEVELOPING BY 05Z...LOWERING TO
LIFR BY 10Z. IMPROVEMENT TO VFR BY 15Z. WINDS 5 KT OR LESS THROUGH
13Z.

KHPN FCSTER COMMENTS: IFR CONDS DEVELOPING BY 05Z...LOWERING TO
LIFR BY 08Z. IMPROVEMENT TO MVFR BY 15Z...THEN TO VFR BY 18Z. WINDS
5 KT OR LESS THROUGH 13Z.

KISP FCSTER COMMENTS: OCNL IFR CONDS EARLY...THEN IFR BY 04Z...
THEN TO LIFR BY 06Z. CONDS IMPROVE TO MVFR BY 15Z...THEN TO VFR BY
19Z. SW WINDS 5-7 KT.

.OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
.TUE NGT...BECOMING IFR WITH FOG AND STRATUS.
.WED-FRI...SCT SHOWERS/TSTMS. AT NIGHT...IFR POSSIBLE
WITH STRATUS/FOG.
.SAT...VFR.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
SEAS NOT QUITE AS HIGH AS FORECAST WITH THE 5 FT SEAS MAINLY
ACROSS THE OUTER OCEAN FORECAST WATERS. SUSTAINED SOUTH TO
SOUTHWEST WIND NOT AS STRONG AND HAVE LOWERED A FEW KNOTS. SWELL
PERIOD IS UNDER 10 SECONDS...AROUND 7...SO HAVE REMOVED SWELL AND
ROUGH CONDITIONS WORDING.

WILL LEAVE ADVISORY AS POSTED WITH THE WESTERN ZONE FROM SANDY
HOOK TO FIRE ISLAND EXPIRING AT MIDNIGHT...AND THROUGH THE NIGHT
EAST OF FIRE ISLAND INLET.

DENSE FOG CONTINUES AND ADVISORY REMAINS THROUGH TUE MORNING. THE
DENSE FOG COULD LAST ON THE OCEAN INTO TUE NIGHT OR WED MORNING.

SEAS AND SOUTHERLY WINDS WILL INCREASE ON WED VIA A TIGHTENING
PRESSURE GRADIENT. SEAS COULD BE ABOVE 5 FT BY WED
AFTERNOON...WITH 25 KT WIND GUSTS POSSIBLE ON THE OCEAN WATERS BY
WED EVENING. A COLD FRONT WILL MOVE ACROSS LATE THU NIGHT...WITH
HIGH PRESSURE BUILDING IN AT THE SURFACE ON FRI. WINDS COULD BE
BELOW SCA CRITERIA BY EARLY FRI MORNING...WITH SEAS REMAINING
ABOVE 5 FT THROUGH FRI AFTERNOON. SOME UNCERTAINTY EXISTS ON THE
TIMING OF THE COLD FROPA AND THE INCREASE OF WINDS ON WED.
-- End Changed Discussion --

&&

.HYDROLOGY...
ISOLD TO WIDELY SCT SHOWERS OR TSTMS LATE IN THE DAY TUE...MAINLY
INLAND. IMPACTS WILL BE MINIMAL.

SCT SHOWERS/TSTMS WED-THU WILL BE CAPABLE OF PRODUCING LOCALLY HEAVY
RAINFALL...WITH THE BEST CHANCES NORTH/WEST OF NYC. TOTAL BASIN
AVG QPF FOR WED-THU COULD BE 1/4 TO 1/2 INCH...WITH LOCALLY HIGHER
AMTS IN TSTMS.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...DENSE FOG ADVISORY UNTIL 10 AM EDT TUESDAY FOR CTZ009>012.
NY...DENSE FOG ADVISORY UNTIL 10 AM EDT TUESDAY FOR NYZ071-078>081-
     177-179.
NJ...NONE.
MARINE...DENSE FOG ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ330-335-338-
     340-345.
     DENSE FOG ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ350-353-355.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT TUESDAY
     FOR ANZ350-353.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL MIDNIGHT EDT
     TONIGHT FOR ANZ355.
-- End Changed Discussion --

&&

$$