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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 171426
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1026 AM EDT MON JUN 17 2013

.SYNOPSIS...
A COLD FRONT MOVES INTO THE REGION TODAY...THEN STALLS OUT NEARBY
INTO TUESDAY. A COLD FRONT PUSHES SOUTHEAST OF THE REGION TUESDAY
NIGHT...WITH A WEAK WAVE OF LOW PRESSURE PASSING SOUTH OF THE
REGION ON WEDNESDAY. HIGH PRESSURE RETURNS FOR THE REST OF THE
WEEK. A WARM FRONT APPROACHES THE AREA ON SUNDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
UPDATED GRIDS TO REFLECT CURRENT TRENDS. LOWERED SKY COVER THROUGH
THE EARLY AFTERNOON AS MID-HIGH LEVEL CLOUDS HAVE SHIFTED
OFFSHORE. FORECAST HIGH TEMPERATURES AROUND 5 DEGREES ABOVE NORMAL
ACCEPTED.

OTHERWISE...A WEAK 700-500 HPA SHORTWAVE CURRENTLY OVER THE OHIO VALLEY
MOVES ACROSS THE AREA THIS AFTERNOON/EVENING. THIS COUPLED WITH A
WEAK COLD FRONT SAGGING INTO THE AREA SHOULD SERVE AS THE TRIGGER
FOR A FEW SHOWERS/TSTORMS...ESPECIALLY ACROSS THE INTERIOR.
1000-1500 J/KG OF CAPE IS FORECAST BY THE RAP/NAM/SREF. LATEST 12Z
NAM AND HRRR RUNS SHOW SCATTERED CONVECTION DEVELOPING NORTH OF
THE REGION AND MOVING INTO THE INTERIOR THIS EVENING. MODEL
SOUNDINGS INDICATE DRY AIR THAT MAY SERVE TO INHIBIT CONVECTIVE
DEVELOPMENT. HAVE CONTINUED TO FORECAST CHANCE POPS ACROSS THE
INTERIOR WITH SLIGHT CHANCE POPS FURTHER SOUTH DUE TO AFTERNOON SEA
BREEZES AND LOWER INSTABILITY.

IN ADDITION TO THE AFOREMENTIONED CAPE...FORECAST TO HAVE 40-50
KT OF BULK SHEAR. A STRONG TO POSSIBLY SEVERE STORM CANNOT BE
RULED OUT ACROSS THE INTERIOR WITH FORECAST BULK SHEAR VALUES 40-50 KT
AND WET BULB ZERO HEIGHTS 7500-9500 FT COULD SEE SOME SMALL TO
POSSIBLY LARGE HAIL ALONG WITH GUSTY WINDS.

THERE IS A MODERATE RISK OF RIP CURRENTS INTO THIS EVENING.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
-- Changed Discussion --
ANY CONVECTION SHOULD DIE OUT EARLY THIS EVENING WITH EXIT OF
700-500 HPA SHORTWAVE AND LOSS OF SOLAR HEATING. FOR LOWS TONIGHT
USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER
TEMPERATURES...WITH READINGS FORECAST TO BE A FEW DEGREES ABOVE NORMAL.

700-500 HPA NORTHERN STREAM TROUGH AXIS MOVES IN TUESDAY...AND
SHOULD ACT ON STALLED FRONTAL BOUNDARY TO PRODUCE AT LEAST SCT SHRA/TSRA
ACROSS THE TRI-STATE. STILL SOME VARIATION ON THE MODELS IN TERMS
OF COVERAGE/STRENGTH SO KEPT POPS AT CHANCE FOR NOW.

MAIN QUESTION IS STRENGTH OF INSTABILITY. NAM HAS 1500-2500 J/KG
OF CAPE...WITH THE GFS ONLY AROUND 500 J/KG AND THE ECMWF
SOMEWHERE IN BETWEEN.

THE REGION WILL ALSO BE IN THE RIGHT REAR QUADRANT OF A 75+ KT 300
HPA JET...HAVE 40-50 KT OF BULK SHEAR...AND FAIRLY DECENT LOW
LEVEL HELICITY. SO IF THE HIGHER INSTABILITY IN THE NAM CAN BE
REALIZED...HAVE THE POTENTIAL FOR SOME STRONG TO POSSIBLY SEVERE
STORMS. IF NOT...THEN ONCE AGAIN SHOULD SEE MAINLY AIRMASS
TSTMS...WITH MAYBE AN ISOLD LOW TOPPED SUPERCELL LIKE TODAY.


FOR HIGHS TUESDAY USED A BLEND OF MIXING DOWN FROM 900 HPA NEAR
THE COAST TO 825 HPA WELL INLAND...WITH NAM 2-METER TEMPERATURES
AND A BLEND OF MAV/MET GUIDANCE. EXPECT HIGHS TO BE AROUND 5
DEGREES ABOVE NORMAL.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
MODELS COMING INTO SOMEWHAT BETTER AGREEMENT WITH EVOLUTION OF THE
MAIN SYNOPTIC FEATURES FOR MIDWEEK...WITH A STRONG UPPER LOW CURLING
THROUGH EASTERN CANADA AND A COLD FRONT PUSHING SOUTHEAST OF THE
REGION TUESDAY NIGHT. THIS SHOULD HAVE ANY SHRA/TSRA ACTIVITY
TUESDAY NIGHT WEAKENING AND GRADUALLY SINKING SE OF THE REGION.

FOR WED...MODELS ARE KEYING IN ON SHORTWAVE ENERGY CURRENTLY OVER
THE CANADIAN ROCKIES...ROUNDING THE BASE OF THE NE US TROUGH...AND
HELPING TO INDUCE A WAVE OF LOW PRESSURE ALONG THE COLD FRONT. AT
THIS POINT...IT APPEARS WE SHOULD BE MAINLY DRY...BUT COULD BE ON
THE NORTHERN FRINGE OF ANY PRECIP WITH THIS FEATURE. IT WILL HAVE TO
BE WATCHED. IF NOTHING ELSE...A BIT MORE CLOUD COVER AND ONSHORE
FLOW TO THE NORTH OF THE LOW WOULD HOLD TEMPS BELOW SEASONABLE
LEVELS.

THEREAFTER...MODELS IN DECENT AGREEMENT WITH MEAN TROUGHING
CONTINUING OVER THE NORTHEAST...WITH CANADIAN HIGH PRESSURE GRADUALLY
BUILDING INTO THE REGION AND IN CONTROL THROUGH SATURDAY. THIS WILL
RESULT IN FAIR AND SEASONABLE WARM CONDITIONS THROUGH THE PERIOD.
WEAK PIECES OF SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH
COULD SET OFF ISOLATED PULSE SHRA/TSRA ACTIVITY EACH AFT/EVE...MAINLY
OFF THE NW HIGHER ELEVATIONS.

HEIGHTS MAY BEGIN TO BUILD THIS WEEKEND INTO EARLY NEXT WEEK...WITH
A TREND TOWARDS MORE SUMMER LIKE WEATHER. THIS WOULD ALSO BRING
POTENTIAL FOR MCS ACTIVITY AS THE REGION LIES ON THE SOUTHERN EDGE
OF THE WESTERLIES.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
A SURFACE TROUGH REMAINS OVER THE TERMINALS TODAY.

SOUTHWEST WINDS LESS THAN 10 KT TO START. SPEEDS GRADUALLY INCREASE
THIS MORNING AND INTO THE AFTERNOON WITH SPEEDS BETWEEN 8-15 KT
SUSTAINED. SEA BREEZES LIKELY AT THE COASTAL TERMINALS THIS
AFTERNOON. OCCASIONAL GUSTS TO NEAR 20 KT ARE POSSIBLE TODAY.

AN AFTERNOON SHOWER OR TSTM POSSIBLE INLAND. TIMING AND PLACEMENT
TOO LOW TO INCLUDE IN THE TAFS FOR NOW.

     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 MAY BE NEEDED TO ADJUST TIMING OF
ANY WIND SHIFTS. AN OCCASIONAL GUST TO 20 KT CAN NOT BE RULED OUT.

KLGA FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF
ANY WIND SHIFTS. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE
RULED OUT.

KEWR FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF
ANY WIND SHIFTS.

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

KTEB FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF
ANY WIND SHIFTS.

KHPN FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF
ANY WIND SHIFTS.

KISP FCSTER COMMENTS: AMENDMENTS MAY BE NEEDED TO ADJUST TIMING OF
ANY WIND SHIFTS. AN OCCASIONAL GUST INTO THE UPPER TEENS CAN NOT BE
RULED OUT.

.OUTLOOK FOR 12TUE THROUGH FRI...
.TUE...SCT SHOWERS AND ISOLD-SCT TSTMS COULD BRING MVFR OR LOWER
CONDITIONS.
.WED-FRI...VFR.
-- End Changed Discussion --

&&

.MARINE...
WAVEWATCH RUNNING AROUND 1 FT TOO HIGH...SO ADJUSTED DOWN A FT OR
SO.

WITH A RELATIVELY LIGHT PRESSURE GRADIENT OVER THE REGION EXPECT
WINDS TO BE 10 KT OR LESS THROUGH TUESDAY...OUTSIDE OF AFTERNOON
SEABREEZES EACH DAY AND ANY THUNDERSTORMS. WAVES...EVEN WITH A
PERSISTENT 2 FT SWELL SHOULD REMAIN BELOW SCA LEVELS ON THE OCEAN
WATERS THROUGH TUESDAY.

MARGINAL SCA SEAS ARE POSSIBLE WEDNESDAY WITH A WEAK WAVE OF LOW
PRESSURE MOVING TO THE SOUTH OF THE REGION. OTHERWISE...SUB SCA
CONDITIONS ARE LIKELY FOR MID THROUGH LATE WEEK AS HIGH PRESSURE BUILDS
IN.

&&

.HYDROLOGY...
BASIN AVERAGE QPF FROM ANY SHRA/TSTMS THIS AFTERNOON/EARLY EVENING
SHOULD BE LESS THAN .1 INCHES. WITH PRECIPITABLE WATERS AROUND 1
INCH...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...MALOIT/NV
NEAR TERM...DS
SHORT TERM...MALOIT
LONG TERM...NV
AVIATION...BC
MARINE...MALOIT/NV
HYDROLOGY...MALOIT/NV