AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1122 PM EDT THU JUL 7 2011

.SYNOPSIS...
A FRONTAL BOUNDARY WILL SLOWLY DRIFT SOUTH OF LONG ISLAND LATE
TONIGHT AND REMAIN JUST SOUTH OF THE AREA THROUGH SATURDAY. WEAK
AREAS OF LOW PRESSURE WILL RIDE ALONG THE FRONT. HIGH PRESSURE
THEN BUILDS IN FOR THE WEEKEND...SLIDING OFFSHORE SUNDAY NIGHT. A
COLD FRONT APPROACHES FROM THE WEST MONDAY...THEN CROSSES THE AREA
MONDAY NIGHT AND EARLY TUESDAY. HIGH PRESSURE THEN BUILDS IN
THROUGH THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
0230Z UPDATE...ADJUSTMENTS TO TEMPS/DEWPOINTS/SKY/POP GRIDS TO
REFLECT LATEST TRENDS. STILL HAVE POPS NO HIGHER THAN CHANCE...BUT
IT LOOKS LIKE THAT THE BETTER CHANCES OF RAIN OVERALL ARE LATE
TONIGHT.

IT APPEARS THAT THE FRONT HAS SAGGED SOUTH A LITTLE IN THE PAST
HOUR OR TWO...AND STRETCHES ACROSS THE NORTHERN FRINGE OF THE CWA.
MODELS SHOW MOISTURE INCREASING FROM THE WEST AS THE NIGHT
PROGRESSES...BUT STILL AN ISOLATED SHOWER MAY POP UP ALONG THE
OLD SEA BREEZE BOUNDARY OVER CT AT ANY GIVEN TIME.

ALSO ADDED IN PATCHY FOG TO THE GRIDS FOR EASTERN LONG ISLAND
THROUGH SE CT.

MAV/MET GUIDANCE IN GOOD AGREEMENT OVERNIGHT...AND WAS USED FOR LOWS.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRONT REMAINS STALLED TO THE SOUTH FRIDAY...WITH WEAK WAVES OF
LOW PRESSURE DEVELOPING SOUTHWEST OF THE REGION AND RIDING ALONG
THE FRONT. WITH NO SIGNIFICANT CHANGES TO THE OVERALL SYNOPTIC
SCENARIO...A PRIMARILY PERSISTENCE FORECAST CONTINUES THROUGH
FRIDAY AFTERNOON WITH CHANCE POPS OVER THE REGION THROUGH THE DAY.
MODEL CONSENSUS DEVELOPS A CLOSED LOW NEAR THE DELMARVA LATE IN
THE DAY...WITH THE GFS BEING MORE AGGRESSIVE THAN THE ECMWF AND
THE NAM IN CLOSING OFF THE LOW AND MOVING IT TOWARDS THE COAST.
POPS INCREASE TO LIKELY OVER SOUTHWESTERN LATE IN THE DAY AS THE
LOW BEGINS TO TAKE SHAPE TO OUR SOUTHWEST. ONGOING CLOUD COVER
WILL LIMIT OVERALL INSTABILITY...BUT AROUND 500 J/KG OF CAPE AND
POTENTIAL GREATER INSTABILITY ALOFT WILL BE ENOUGH TO KEEP TSTMS
IN THE FORECAST.

COOLER HIGH TEMPS LIKELY FRIDAY WITH ABUNDANT CLOUD
COVER...ONSHORE FLOW AND SHOWERS/THUNDERSTORMS MOVING INTO THE
REGION. IN THE AFTERNOON...HIGHS WILL RANGE FROM THE UPPER 70S TO
LOW 80S.

THE LOW PASSES SOUTH OF THE REGION FRIDAY NIGHT...THEN QUICKLY
MOVES INTO THE NEW ENGLAND COASTAL WATERS BY SATURDAY MORNING.
POPS GRADUALLY DIMINISH OVERNIGHT. LOWS IN THE 60S EXPECTED.

THERE IS A MODERATE RISK FOR RIP CURRENTS AT OCEAN-FACING BEACHES
ON FRIDAY.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
A COLD FRONT WILL REMAIN SOUTH OF THE REGION ON SATURDAY AS A
WAVE OF LOW PRESSURE TRAVELING ALONG THIS FRONT DEPARTS. HIGH
PRESSURE NORTHWEST OF THE CWA BUILDS INTO THE REGION THROUGH THE
WEEKEND AND INTO MONDAY MORNING. THEREFORE...WILL KEEP CONDITIONS
DRY THROUGH THIS TIME PERIOD.

A FRONTAL SYSTEM THEN APPROACHES EARLY IN THE NEW WEEK...POSSIBLY
BRINGING SHOWERS AND THUNDERSTORMS TO THE REGION MON AFTERNOON/NIGHT
THROUGH TUE...THEN DRY WX RETURNS FOR WEDNESDAY AND THURSDAY AS HIGH
PRESSURE BUILDS BACK INTO THE REGION.

TEMPERATURES THROUGH THE EXTENDED PERIOD WILL REMAIN AT OR ABOVE
NORMAL.

&&

.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
STATIONARY FRONT WAS LOCATED JUST NORTH OF NYC TERMINALS AT 03Z
WITH A LIGHT S/SE WIND AT THE COAST...AND A LIGHT AND VARIABLE
WIND AT THE INLAND TERMINALS. THE FRONT IS FORECAST TO DROP
SLOWLY SOUTH OVERNIGHT IN RESPONSE TO LOW PRESSURE DEVELOPMENT
OVER THE MID ATLANTIC STATES. THIS WILL ALLOW FOR A LIGHT E/NE
FLOW TO DEVELOP BY MORNING. THE FLOW REMAINS WEAK ON FRI...VARYING
FROM E TO SE AT 5 TO 10 KT.

WITH HIGH LEVEL CLOUDS ACROSS THE AREA AND A WEAK ONSHORE
FLOW...STRATUS SEEMS UNLIKELY OVERNIGHT...BUT SOME PATCHY MVFR
FOG IS EXPECTED. STRATUS FORMATION WILL NEED TO BE WATCHED AT KGON
AND KISP WHERE DEW POINTS IN THE LOWER 70S RESIDE.

SCATTERED SHOWERS WILL DEVELOP IN THE MORNING AND WILL LIKELY
CONTINUE THROUGH THE DAY. EMBEDDED THUNDERSTORMS ARE POSSIBLE AS
WELL.

AMENDMENTS ARE LIKELY ON FRI DUE TO UNCERTAINTY IN TIMING
OF CONVECTION AND VARIABILITY OF WINDS WITH FRONTAL BOUNDARY IN
CLOSE PROXIMITY.

OUTLOOK FOR 00Z FRIDAY THROUGH TUESDAY...

FRI NIGHT...SUB VFR IN SHRA/TSRA LIKELY.
SAT...IMPROVING CONDITIONS BEHIND A FRONT.
SUN-MON...VFR.
TUE...CHANCE OF MVFR OR LOWER IN THE MORNING. TSRA POSSIBLE AHEAD
OF A COLD FRONT.

&&

.MARINE...
SCT CONVECTION POSSIBLE TONIGHT...OTHERWISE...WINDS/WAVES WILL BE
TRANQUIL.

A WAVE OF LOW PRES APPROACHES ON FRIDAY AND THEN PASSES THROUGH THE
WATERS FRIDAY NIGHT INTO EARLY SATURDAY. CHANCES FOR CONVECTION INCREASES
THROUGHOUT THE AFTERNOON AND PEAK IN THE EVENING. WINDS/WAVES WILL
REMAIN BELOW SCA CRITERIA.

HIGH PRESSURE WILL THEN BUILD OVER THE WATERS SUNDAY AND MONDAY.
A COLD FRONT WILL PUSH ACROSS THE WATERS ON TUESDAY. ANOTHER AREA
OF HIGH PRESSURE WILL BUILD OVER THE AREA WEDNESDAY AND THURSDAY.

SOME 5 FT SEAS WILL BE POSSIBLE WITH THE DEPARTURE OF THE LOW
PRESSURE SYSTEM SATURDAY AND SUNDAY. OTHERWISE...CONDITIONS ARE
EXPECTED TO REMAIN BELOW SCA LEVELS.

&&

.HYDROLOGY...
NO SIGNIFICANT WIDESPREAD PRECIPITATION IS EXPECTED AT THIS TIME.
LOCALLY HEAVY RAINFALL IS HOWEVER POSSIBLE WITH ANY STRONGER
CONVECTION. HOWEVER...IF THE ECMWF ENDS UP BEING CORRECT WITH THE
STRENGTH AND LOCATION OF THE COASTAL LOW TRACKING TO OUR S FRIDAY
NIGHT...THERE IS THE POTENTIAL FOR A SOAKING RAIN OF 0.5-1
INCH...WITH LOCALLY HIGHER AMOUNTS IN STRONGER EMBEDDED
CONVECTION. WHILE THIS DOES NOT APPEAR LIKELY...THE POSSIBILITY IS
HIGH ENOUGH THAT IT WARRANTS WATCHING AT THIS TIME.

&&

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

&&

$$