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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 150300
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1100 PM EDT TUE MAY 14 2013

.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN AND MOVE EAST TONIGHT INTO WEDNESDAY AS A
WARM FRONT APPROACHES. THE WARM FRONT WILL MOVE ACROSS THE AREA
EARLY WEDNESDAY EVENING...FOLLOWED BY A COLD FRONTAL PASSAGE
THURSDAY NIGHT. HIGH PRESSURE OVER THE UPPER MIDWEST BUILDS
SOUTHEAST ACROSS THE GREAT LAKES AT THE END OF THE WEEK AND INTO
THE NORTHEAST FOR THE UPCOMING WEEKEND. A FRONTAL BOUNDARY WILL
SAG SOUTH DURING THIS TIME ACROSS THE MID ATLANTIC STATES. AS THE
HIGH BUILDS WELL OFFSHORE BY EARLY NEXT WEEK...THE FRONT WILL THEN
RETURN NORTH AS A WARM FRONT.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
MAINLY SKC ACROSS THE CWA AT 930 PM. SHIELD OF CLOUDS SHOWS UP ON
STLT OVER PA. EWD PROGRESS IS SLOW...SO HAVE ADJUSTED THE TIMING
OF INCREASING CLOUDS OVERNIGHT. MINOR ADJUSTMENTS TO TEMPS AS A
RESULT. DESPITE THE INCREASE IN CLOUDS FROM W TO E LATE...EXPECT A
DRY OVERNIGHT. OVERNIGHT LOWS TONIGHT WILL FALL INTO THE 40S AND
LOWER 50S. NORTH AND WEST OF NYC MAY SEE SOME LOWS FALL INTO THE
UPPER 30S.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
A LOW PRESSURE SYSTEM...BOTH AT THE SURFACE AND ALOFT WILL TREK
FROM THE GREAT LAKES REGION INTO SOUTHEASTERN CANADA THROUGH
WEDNESDAY NIGHT. AS IT DOES...A WARM FRONT ASSOCIATED WITH THE LOW
WILL LIFT NORTH ACROSS THE REGION WEDNESDAY MORNING. EXPECT A
MOSTLY CLOUDY DAY WITH THE FRONTAL BOUNDARY NEAR THE REGION. IN
ADDITION...SHOWERS ARE EXPECTED TO DEVELOP DURING THE AFTERNOON.
WILL HAVE INCREASING POPS THROUGH THE MORNING BEFORE SHOWERS
BEFORE THEY BECOME LIKELY BY AFTERNOON. THERE WILL BE SOME
ELEVATED INSTABILITY AROUND THE REGION...SO WILL INCLUDE ISOLATED
THUNDER IN THE FORECAST AS WELL.

AS THE FRONT LIFTS NORTH OF THE REGION LATE IN THE DAY AND
OVERNIGHT...POPS WILL GRADUALLY DIMINISH OVERNIGHT...HOWEVER WONT GO
COMPLETELY DRY. SKIES WILL ALSO START TO CLEAR OUT FROM WEST TO
EAST.

MAV/MET GUIDANCE IN FAIRLY GOOD AGREEMENT AND USED ALONG WITH A
BLEND OF THE PREVIOUS FORECAST. HIGHS ON WEDNESDAY WILL REACH THE
MIDDLE AND UPPER 60S...WITH WEDNESDAY NIGHT LOWS FALLING INTO THE
UPPER 40S AND 50S.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
AN UPPER TROF ACROSS EASTERN CANADA AND THE NE AT THE START OF THE
PERIOD WILL LIFT SLOWLY N AND E INTO EARLY NEXT WEEK....WHILE AN
AMPLIFYING RIDGE OVER THE MID SECTION OF THE COUNTRY BUILDS TOWARD
THE EASTERN SEABOARD. AT THE SURFACE...HIGH PRESSURE BUILDS SE FROM
THE UPPER MIDWEST AND GREAT LAKES STATES AND ACROSS THE NE OVER THE
WEEKEND. THIS WILL RESULT IN A PERIOD OF DRY WEATHER. THE 12Z GFS
DOES SHOW A CONVECTIVE COMPLEX ROUNDING THE UPPER RIDGE AND DROPPING
ACROSS THE NORTHERN MID ATLANTIC REGION ON SAT...GRAZING THE
FORECAST AREA. THIS SEEMS TO BE DISPLACED TOO FAR NORTH BASED ON THE
POSITION OF THE FRONTAL BOUNDARY TO THE SOUTH. THUS...A DRY SOLUTION
IS PREFERRED AT THIS TIME FOR SAT.

AS THE HIGH BUILDS TO THE EAST OVER THE WEEKEND...A RETURN EASTERLY
FLOW DEVELOPS...BECOMING MORE SLY SUN INTO MON WITH THE FRONT OVER
THE MID ATLANTIC STATES RETURNING NORTH A WARM FRONT. THE GFS IS A
BIT SLOWER WITH THE UPPER RIDGE AXIS AND EVEN FORMS A WAVE OF LOW
PRESSURE ALONG THE FRONT TO THE SOUTH. THIS ENHANCES THE LOW-LEVEL
RIDGING ACROSS THE AREA. THE ECMWF BRINGS THE WARM FRONT NORTH OF
THE AREA ON MON. THE GFS DOES HAVE SUPPORT OF ITS ENSEMBLE AS WELL
AS THE GLOBAL GEM. THAT BEING THE CASE THERE WILL BE AN INCREASE IN
CLOUD COVER LATE IN THE WEEKEND AND INTO EARLY NEXT WEEK WITH LOW
CHANCE POPS TO ACCOUNT FOR THE DEVELOPING WARM ADVECTION PATTERN.
THIS MAY BE A BIT AGGRESSIVE AND SHOULD THE SLOWER SOLUTION GFS
VERIFY...THE CLOUDS AND PCPN MAY NEED TO BE DELAYED EVEN FURTHER.

AS FOR TEMPS...THU AND FRI WILL BE ABOVE NORMAL IN A WESTERLY FLOW
WITH A RETURN TO MORE SEASONABLE TEMPS OVER THE WEEKEND INTO EARLY
NEXT WITH AN INCREASE IN CLOUD COVER AND ONSHORE FLOW. SHOULD THE
RIDGING BE MORE DOMINANT WITH LESS CLOUD COVER...THEN EVEN THE TEMPS
MAY NEED TO BE ADJUSTED UPWARDS.

&&

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
VFR CONDITIONS WITH HIGH PRESSURE TONIGHT...FOLLOWED BY A WARM
FRONT PASSING THROUGH WED WITH POSSIBLE MVFR LATE IN THE PERIOD.

THROUGH THE OVERNIGHT...THERE WILL BE LIGHT WINDS 10 KT OR LESS
WITH MID AND HIGH LEVEL CLOUDS INCREASING.

CLOUDS INCREASE ON WED...THICKENING AND LOWERING DURING THE DAY.
MAINLY VFR CONDITIONS ARE EXPECTED BUT THERE WILL BE A CHANCE OF
MVFR CONDITIONS LATER IN THE AFTERNOON WITH SHOWER ACTIVITY. THIS
WILL LIKELY BE INTERMITTENT IN FREQUENCY. THERE COULD BE AN
ISOLATED THUNDERSTORM AS WELL IN THE LATE AFTERNOON TO EARLY
EVENING BUT FOR THIS...CONFIDENCE IS TOO LOW TO INCLUDE IN TAFS
AT THE MOMENT.

SOUTHERLY FLOW PICKS UP ON WED...WITH SUSTAINED SPEEDS OF 10-15 KT
WITH GUSTS IN THE 20-25 KT RANGE. PEAK GUSTS BETWEEN 15 AND 23Z
UP TO 25-30 KT AT TIMES WILL BE POSSIBLE.

AMENDMENTS LIKELY ON WED TO REFINE TIMING OF SHRA WHICH COULD
OCCUR AROUND 1-2 HOURS EARLIER OR LATER THAN FORECAST. MVFR COULD
EXTEND IN THE EVENING WED.

.OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...
.WED NIGHT...MVFR OR LOWER POSSIBLE IN LEFTOVER SHRA/PATCHY FOG IN
THE EVENING. WINDS BECOMING W THEN NW AND LOWERING IN SPEED.
IMPROVING CONDITIONS LATE.
.THU...VFR. CHC MVFR IN SCT SHOWERS EARLY AM.
.FRI-SUN...VFR.
-- End Changed Discussion --

&&

.MARINE...
SUB-SCA CONDITIONS ARE FORECAST THROUGH TUE NIGHT AS HIGH
PRESSURE MOVES ACROSS.

SCA CONDITIONS BECOME LIKELY WEDNESDAY AFTERNOON AND NIGHT AS
SOUTHERLY FLOW INCREASES TO AROUND 20 KT BY LATE IN THE DAY ON
WEDNESDAY. A FEW GUSTS TO 25 KT CAN NOT BE RULED OUT. SEAS WILL
BUILD TO 5-7 FT. SCA WILL BE ISSUED FOR THE OCEAN WATERS FOR THIS
TIME FRAME.

SCA SEAS MAY LINGER INTO THU NIGHT...BUT WITH A W/NW FLOW THU INTO
FRI AND HIGH PRESSURE APPROACHING FROM THE WEST...SEAS WILL BE
SUBSIDING. SUB-SCA CONDITIONS ARE FORECAST OVER THE WEEKEND AS HIGH
PRESSURE BUILDS ACROSS THE WATERS. AN E/SE FLOW DEVELOPS LATE SAT
INTO SUN AT AROUND 10 KT.

&&

.HYDROLOGY...
NO SIGNIFICANT WIDESPREAD PRECIPITATION IS EXPECTED THROUGH THE
END OF THE WEEK. SOME TSTMS WED AFTERNOON/EVENING COULD PRODUCE
LOCALLY UP TO 1/2 INCH OF RAIN.

NO SIGNIFICANT WIDESPREAD PRECIPITATION IS EXPECTED THROUGH EARLY
NEXT WEEK.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON WEDNESDAY TO 6 AM EDT THURSDAY
     FOR ANZ350-353-355.

&&

$$
SYNOPSIS...BC/DW
NEAR TERM...BC/JMC
SHORT TERM...BC
LONG TERM...DW
AVIATION...JM
MARINE...BC/DW
HYDROLOGY...BC/DW