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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 111652
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1252 PM EDT FRI JUL 11 2014

.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE AREA TODAY AND SATURDAY...THEN
WEAKENS AND MOVES FARTHER OFFSHORE SUNDAY. MEANWHILE...A COLD
FRONT APPROACHES FROM THE NORTHWEST...SLOWLY MOVING IN MONDAY INTO
MONDAY NIGHT AND THEN STALLING WITHIN THE REGION THROUGH EARLY
NEXT WEEK. SMALL WEAK LOWS FORM ALONG THE FRONT WITH ONE
EVENTUALLY PUSHING THE FRONT EAST OF THE REGION BY NEXT WEDNESDAY
NIGHT INTO NEXT THURSDAY WITH HIGH PRESSURE FOLLOWING.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
MINOR CHANGES TO THE FORECAST THIS AFTERNOON TO ACCOUNT FOR TIMING
OF SEA BREEZE AND BUMPING UP DEWPOINTS SLIGHTLY PER OBSERVATIONS.
ALSO ADDED A SLIGHT CHANCE OF SHOWERS FOR NEW LONDON COUNTY AS
THERE APPEARS TO BE JUST ENOUGH INSTABILITY TO POP UP A SHOWER OR
TWO THIS AFTERNOON PER RECENT TRENDS IN VISIBLE SAT IMAGERY NEAR
THE SEA BREEZE.

OTHERWISE...HIGH PRESSURE WILL BE OVER THE REGION TODAY WITH
STATIONARY FRONT JUST OFF TO OUR SOUTH. A SHORTWAVE AND WEAKENING
UPPER ALSO PASS THROUGH TODAY...BUT IT LOOKS LIKE MOISTURE WILL BE
MORE LIMITED AS COMPARED TO YESTERDAY. IN ADDITION...A LIGHT
ONSHORE FLOW WILL ALLOW FOR SEA BREEZES TO DEVELOP AND STABILIZE
MUCH OF THE AREA...SO NOT EXPECTING SHOWERS TO DEVELOP HERE IN
RESPONSE TO THE LIFT AND CYCLONIC FLOW ALOFT.

A MAV/NAM MOS BLEND LOOKED GOOD FOR HIGHS...WHICH WILL BE NEAR
NORMALS.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE SYNOPTIC PATTERN DOESN`T CHANGE ALL THAT MUCH DURING THIS
PERIOD. HIGH PRESSURE WILL HOWEVER DRIFT FARTHER OUT TO SEA WITH
MORE OF A RETURN S TO SW FLOW AND A LITTLE MORE HUMID AIRMASS.
MOISTURE STILL APPEARS TO BE LACKING FOR ANY MID LEVEL SHORTWAVES TO
TRIGGER SHOWERS. WILL CONTINUE WITH A DRY FORECAST. MAV/NAM MOS
NUMBERS FOR HIGHS AND LOWS WERE SIMILAR AGAIN...AND A BLEND WAS USED.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
FOR THE TIME PERIOD OF SUNDAY THROUGH THURSDAY...GENERALLY THERE
WILL BE A BUILDING RIDGE IN THE WESTERN U.S. AND A DEEP CUTOFF LOW
IN MANITOBA/ONTARIO. MULTIPLE LOBES OF VORTICITY MAXIMA WILL BE
WITHIN THE CUTOFF LOW. ONE SPOKE ROTATES INTO THE WESTERN GREAT
LAKES SUNDAY NIGHT...IMPINGING ON THE WESTERN U.S. RIDGE. THE MAIN
CUTOFF LOW WILL EVENTUALLY TRAVERSE INTO THE EASTERN GREAT
LAKES...STARTING TO SHIFT NORTH INTO QUEBEC BY MIDWEEK.

ACROSS THE LOCAL AREA...ZONAL MID LEVEL FLOW SUNDAY BECOMES
PROGRESSIVELY MORE AND MORE SOUTHWEST INTO NEXT WEEK...IN RESPONSE
TO AN AMPLIFYING TROUGH TO THE WEST OF THE REGION. THE ASSOCIATED
UPPER LEVEL JET WILL STILL BE NORTH OF AREA SUNDAY WITH A ZONAL
FLOW. THIS JET WILL SLOWLY PUSH MORE SOUTH AND EAST WITH TIME GOING
INTO NEXT WEEK...EVENTUALLY BECOMING A STRONG MERIDIONAL JET BY MID
NEXT WEEK AS IT MOVES INTO THE LOCAL REGION. THIS JET AND ASSOCIATED
TROUGH AXIS MOVE ACROSS LATE NEXT THURSDAY INTO NEXT THURSDAY NIGHT.

AT THE SURFACE...SUNDAY FEATURES WEAKENING HIGH PRESSURE
TRANSLATING FARTHER OFFSHORE WITH A WARM FRONT LIFTING NORTH OF
THE AREA. A PRE-FRONTAL TROUGH AHEAD OF THE COLD FRONT DEVELOPS
AND MOVES IN FROM THE WEST...BECOMING A FOCUS FOR SHOWERS AND
THUNDERSTORMS.

FOR SUNDAY NIGHT...THE PARENT LOW DEEPENS WITHIN QUEBEC WITH
THE ASSOCIATED COLD FRONT APPROACHING FROM NORTHWEST. THE COLD
FRONT MOVES IN ON MONDAY INTO MONDAY NIGHT BUT THEREAFTER THE
PARENT LOW IN QUEBEC MOVES FARTHER AWAY AND FILLS IN. THE RESULT
WILL BE A LACK OF STEERING FLOW AND A STAGNATION AS WELL AS
WEAKENING OF THE FRONT. THE WEAK FRONT LINGERS WITHIN THE REGION
THROUGH MID WEEK.

THE SCENARIO IS ILLUSTRATIVE OF ROUNDS OF SHOWERS AND THUNDERSTORMS
FROM SUNDAY NIGHT THROUGH WEDNESDAY AS WEAK LOWS MOVE ALONG THE
STALLED FRONT. CONVECTION LESS FREQUENT SUNDAY NIGHT BUT BECOMING
MORE FREQUENT MONDAY NIGHT THROUGH WEDNESDAY WHEN MOISTURE
TRANSPORT INCREASES WITH THE INCREASED MERIDIONAL FLOW. THE LAYER
PRECIPITABLE WATERS INCREASE RAPIDLY SUNDAY AND REMAIN RELATIVELY
NEAR 2 INCHES THROUGH MIDWEEK. THIS WILL ALLOW FOR TORRENTIAL
DOWNPOURS WITH SOME SHOWERS AND THUNDERSTORMS.

NEXT WEDNESDAY NIGHT INTO NEXT THURSDAY...THE LAST LOW WILL HELP
PUSH THE FRONT FINALLY EAST OF THE REGION. IN ITS PLACE...HIGH
PRESSURE STARTS TO BUILD IN FROM THE WEST...WITH DRY WEATHER
RETURNING AS MID AND UPPER LEVEL TROUGHS BEGIN TO LIFT NORTH AND
BECOME LESS AMPLIFIED.

THERE IS STILL A LOT OF UNCERTAINTY AND FACTORS SUCH AS THE SPOKES
OF VORTICITY ASSOCIATED WITH THE CUTOFF LOW AND ASSOCIATED UPPER
LEVEL JET THAT COULD RESULT IN TIMING DIFFERENCES OF SHOWERS AND
THUNDERSTORMS WITH SUBSEQUENT FORECASTS. THEREFORE...MUCH OF THE
TIME-FRAME HAS CHANCE WORDING BUT THE HIGHER CHANCES...NEAR 50-55
PERCENT...REPRESENT A TIME PERIOD WHERE THE CONVECTION IS FORECAST
TO BE MORE FREQUENT WITH RELATIVELY HIGHER COVERAGE EXPECTED.

HIGH TEMPERATURES FORECAST ARE NEAR TO SLIGHTLY ABOVE NORMAL ON
AVERAGE ACROSS THE REGION SUNDAY THROUGH TUESDAY AND THEN SLIGHTLY
BELOW NORMAL ON AVERAGE WEDNESDAY AND THURSDAY NEXT WEEK. LOW
TEMPERATURES AT NIGHT ARE FORECAST TO BE SLIGHTLY ABOVE NORMAL
SUNDAY NIGHT THROUGH TUESDAY NIGHT AND TREND TO SLIGHTLY COOLER THAN
NORMAL FOR NIGHTS THEREAFTER.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
MORNING TAFS ON TRACK...SO NO SIGNIFICANT CHANGES MADE TO THE
FORECAST. WILL UPDATE THE INITIAL HOUR OR SO BASED ON CURRENTS
OBS AND TRENDS.

OTHERWISE...HIGH PRESSURE BUILDS OVER THE AREA THROUGH TONIGHT.

HIGH CONFIDENCE IN VFR THROUGH THE TAF PERIOD.

WINDS BECOME NNE-NE AT UNDER 10 KT INTO EARLY THIS AFTERNOON. A
SEA BREEZE DEVELOPS AROUND MIDDAY THEN PUSHES INLAND...REACHING
ALL TERMINALS BUT KSWF BY LATE-MID AFTERNOON. WINDS BECOME LIGHT
AND VARIABLE AGAIN BY EARLY THIS EVENING...AND REMAIN SO THROUGH
THE NIGHT.

 ...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 SEA BREEZE...AND ONSET OF LIGHT
AND VARIABLE WINDS...COULD BE OFF +/- 1-2 HOURS.

KLGA FCSTER COMMENTS: TIMING OF SEA BREEZE...AND ONSET OF LIGHT
AND VARIABLE WINDS...COULD BE OFF +/- 1-2 HOURS.

KEWR FCSTER COMMENTS: TIMING OF SEA BREEZE...AND ONSET OF LIGHT
AND VARIABLE WINDS...COULD BE OFF +/- 1-2 HOURS.

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

KTEB FCSTER COMMENTS: TIMING OF SEA BREEZE...AND ONSET OF LIGHT
AND VARIABLE WINDS...COULD BE OFF +/- 1-2 HOURS.

KHPN FCSTER COMMENTS: TIMING OF SEA BREEZE...AND ONSET OF LIGHT
AND VARIABLE WINDS...COULD BE OFF +/- 1-2 HOURS.

KISP FCSTER COMMENTS: TIMING OF SEA BREEZE...AND ONSET OF LIGHT
AND VARIABLE WINDS...COULD BE OFF +/- 1-2 HOURS.

.OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY...
.SATURDAY-SUNDAY MORNING...VFR.
.SUNDAY AFTERNOON-TUESDAY...SCT TO POSSIBLY NUMEROUS SHRA/TSTMS.
STRONGER TSTMS DURING THIS TIME FRAME COULD PRODUCE PERIODS OF
MVFR OR LOWER CONDITIONS...LOCALLY HEAVY RAINFALL AND GUSTY WINDS.
-- End Changed Discussion --

&&

.MARINE...
HIGH PRESSURE WILL RESULT IN WINDS AND SEAS REMAINING BELOW SCA
LEVELS THROUGH SATURDAY NIGHT.

INITIALLY SUB SCA CONDITIONS WITH HIGH PRESSURE OFFSHORE WILL
TRANSITION TO A PROLONGED SOUTHERLY FETCH AS HIGH PRESSURE WEAKENS
AND SHIFTS FARTHER OFFSHORE. THERE WILL BE SIMULTANEOUSLY A COLD
FRONT SLOWLY APPROACHING FROM THE WEST. SCA GUSTS NEAR 25 KT ARE
FORECAST FOR PORTIONS OF THE OCEAN SUNDAY AFTERNOON AND SUNDAY NIGHT
AND THIS WILL EVENTUALLY BUILD UP SEAS TO 5 FT SUNDAY NIGHT INTO
MONDAY. THE SEAS WILL FURTHER INCREASE 5-7 FT MONDAY NIGHT THROUGH
TUESDAY...KEEPING SCA CRITERIA CONDITIONS WITH THE SOUTHERLY FETCH.
NON-OCEAN WATERS ARE EXPECTED TO STAY BELOW SCA SUNDAY INTO NEXT
WEEK.

&&

.HYDROLOGY...
NO WIDESPREAD SIGNIFICANT HYDROLOGIC ISSUES EXPECTED THROUGH
SUNDAY MORNING.

THERE IS THE POTENTIAL FOR SIGNIFICANT RAINFALL - WIDESPREAD 1/2
INCH OR MORE - FROM LATE SUNDAY INTO WEDNESDAY AS PRECIPITABLE
WATERS COULD REACH AROUND 2 INCHES FOR AN EXTENDED PERIOD OF TIME -
FAVORING AT LEAST LOCALLY HEAVY RAINFALL. AT THIS TIME THERE IS TOO
MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR SPECIFIC
THREATS...OTHER THAN TO NOTE THE POTENTIAL FOR MINOR URBAN/POOR
DRAINAGE FLOODING AND POSSIBLY LOCALIZED FLASH FLOODING IN AREAS
THAT EXPERIENCE LOCALLY HEAVY RAINFALL.

&&

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

&&

$$
SYNOPSIS...JC/JM
NEAR TERM...JM/GS
SHORT TERM...JC
LONG TERM...JM
AVIATION...MALOIT/MPS
MARINE...JC/JM
HYDROLOGY...JC/JM