-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 240047
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
847 PM EDT THU MAY 23 2013

.SYNOPSIS...
A COLD FRONT MOVES INTO THE AREA TONIGHT...A WAVE OF LOW PRESSURE
THEN FORMS ALONG IT NEAR THE AREA FRIDAY...AND SLOWLY TRACKS TO
THE GULF OF MAINE BY SUNDAY MORNING. HIS LOW SLOWLY THEN LIFTS
INTO THE CANADIAN MARITIMES THROUGH MONDAY. HIGH PRESSURE THEN
BUILDS INTO THE SOUTH THROUGH WEDNESDAY NIGHT. A WARM FRONT WILL
APPROACH ON THURSDAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS CONTINUE TO NE ORIENTED
FROM SW TO NW FROM AROUND NYC METRO NE INTO SW CT. WHILE THIS AREA
CONTINUES TO BE WORKED OVER...THERE IS STILL DEEP MOISTURE IN
PLACE...LOW-LEVEL CONVERGENCE...AND EMBEDDED SHORT SHORT WAVE
ENERGY ALOFT. OVER THE NEXT COUPLE OF HOURS DO EXPECT THIS AREA
TO DISSIPATE DUE AIR MASS STABILIZING. NEXT ORGANIZED ROUND WILL
LIKELY COME TOWARD DAYBREAK WITH THE ACTUAL COLD FRONT AND UPPER
JET DYNAMICS.

TO THE EAST OF THE NYC METRO...ACROSS LI AND SOUTHERN CT...THERE
ARE SIGNS OF A LOW-LEVEL JET AIDING THE DEVELOPMENT OF A BAND OF
CONVECTION. LATEST RADAR SHOWS A LARGE AREA OF SHOWERS SW OF
EASTERN LI...EXTENDING TO EAST OF THE DELMARVA REGION. THIS AREA
DOES NOT HAVE ANY STRONG CONVECTION...BUT THAT MAY CHANGE AS THE
JET INCREASES ACROSS THIS AREA AND THEN TRANSLATES EAST BY EARLY
MORNING.

BOTTOM LINE OVERNIGHT...ANY CONVECTION WILL BE CAPABLE OF BRIEF
HEAVY DOWNPOURS. THE MAIN THREAT LOOKS TO BE MINOR NUISANCE...POOR
DRAINAGE FLOODING...BUT FLASH FLOODING IS POSSIBLE IF THE CONVECTION
CONTINUOUSLY MOVES OR TRAINS OVER THE SAME AREA.

FOR LOWS TONIGHT USED A BLEND OF MAV/MET GUIDANCE WITH NAM 2-METER
TEMPERATURES WITH VALUES AROUND 10 DEGREES ABOVE NORMAL.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
HEAVY RAINFALL THREAT COMES TO AN END FRIDAY MORNING WITH
AFOREMENTIONED 250 HPA JET AXIS SLIDING TO OUR EAST ALONG WITH THE
DEVELOPMENT OF A WAVE OF LOW PRESSURE NEAR THE TRI-STATE AND
TRACKING INTO EASTERN PORTIONS OF THE AREA IN THE AFTERNOON.

CONTINUED MOIST S FLOW INT HE MID LEVELS ALONG WITH LOWS FROM 700
HPA DOWN TO THE SURFACE MOVING OVER THE AREA WILL BRING MAINLY
SHOWERY PRECIPITATION TO THE AREA FROM FRIDAY AFTERNOON INTO
FRIDAY EVENING...QUITE LIKELY TRANSITIONING TO STRATIFORM
PRECIPITATION AFTER MIDNIGHT WITH THE SURFACE LOW SLIDING TO THE
EAST...AND ISENTROPIC LIFT - ALTHOUGH WEAK - TAKING OVER.

FOR HIGHS FRIDAY USED A BLEND OF NAM 2-METER TEMPERATURES WITH A
MIX DOWN FROM 925 HPA PER BUFKIT SOUNDINGS AND MAV AND MET
GUIDANCE. EXPECT HIGHS TO BE NEAR TO SLIGHTLY BELOW NORMAL.

FOR TEMPERATURES FRIDAY NIGHT USED A BLEND OF NAM 2-METER
TEMPERATURES WITH MAV AND MET GUIDANCE WITH LOWS NEAR TO SLIGHTLY
BELOW NORMAL.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
GFS/NAM/ECMWF ALL REASONABLY CLOSE IN THEIR INTENSITY AND MOVEMENT
OF THE CLOSED LOW AND ASSOCIATED LOW PRESSURE MOVING SLOWLY NE THIS
WEEKEND. HAVE SHIFTED FOCUS OF CATEGORICAL POP INITIALLY ON SAT TO
AREAS FROM NYC WEST WHERE HEAVIER COMMA HEAD PRECIP WILL BE
FALLING...THEN E-WARD ACROSS THE REST OF THE AREA INTO THE AFTERNOON
AND EVENING. N-NW WINDS ON THE BACK SIDE OF THE LOW SHOULD BECOME
RATHER BRISK BY SAT AFTERNOON...FALLING JUST SHY OF ADVISORY
CRITERIA AT 15-25 MPH WITH WITH GUSTS 40-45 MPH INTO EARLY SAT
EVENING. CANNOT RULE OUT A TSTM OVER ERN CT/LONG ISLAND VIA SOME
ELEVATED DESTABILIZATION AS DRY SLOT PUNCHES IN FROM THE SW. TEMPS
WILL BE RATHER COOL FOR LATE MAY...WITH HIGHS ONLY 55-60 AND
DROPPING INTO THE 40S SAT NIGHT.

STEADY RAIN SHOULD SHIFT EAST AND TAPER OFF IN INTENSITY SAT NIGHT
AS THE LOW PULLS E OF NEW ENGLAND...BECOMING MORE SHOWERY/ISOLD IN
NATURE ON SUNDAY VIA CYCLONIC LOW LEVEL FLOW AND PASSAGE OF
TRANSIENT MID LEVEL VORTICITY MAXES PINWHEELING AROUND THE UPPER LOW.
STILL COOL AND BREEZY ON SAT WITH HIGHS ONLY UPPER 50S/LOWER
60S...AND GUSTS 25-30 MPH.

DRY WX AND A GRADUAL WARM-UP TO NEAR SEASONABLE LEVELS IS THEN
FORECAST MON-WED AS HIGH PRESSURE MOVES ACROSS. TEMPS ON THU SHOULD
RETURN TO MORE SUMMER-LIKE LEVELS WITH THE APPROACH OF A WARM
FRONT...WHICH COULD BRING AFTERNOON SHOWERS AND POSSIBLE TSTMS
MAINLY TO AREAS WEST OF NYC.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
LOW PRESSURE AND A COLD FRONTAL BOUNDARY WILL MOVE SLOWLY THROUGH
THE AREA TONIGHT INTO FRIDAY...PASSING EAST OF LONG ISLAND LATE IN
THE FORECAST PERIOD. SCATTERED SHOWERS WILL BE LIKELY THIS
EVENING. THERE IS A CHANCE OF ISOLATED THUNDERSTORMS UNTIL AROUND
03Z FOR NEW YORK CITY AND THE TERMINALS TO THE NORTH AND WEST.
SHOWERS BECOME WIDESPREAD LATE THIS EVENING AND CONTINUE THROUGH
THE FORECAST PERIOD.

SOUTHERLY WIND WILL SHIFT TO THE SOUTHWEST AND WEST AS THE FRONT
PASSES THROUGH AFTER 10Z...AND THEN BECOME NORTHERLY AS THE LOW
MOVES FARTHER TO THE EAST DURING FRIDAY.


     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: VARIABLE CEILINGS AND VISIBILITIES IN SHOWERS
AND THUNDERSTORMS THROUGH 03Z...THEN IFR CEILINGS AND MVFR TO IFR
VISIBILITIES IN RAIN AND FOG INTO FRIDAY MORNING. NORTHERLY GUSTS
DEVELOPING IN THE AFTERNOON.

KLGA FCSTER COMMENTS: VARIABLE CEILINGS AND VISIBILITIES IN SHOWERS
AND THUNDERSTORMS THROUGH 03Z...THEN IFR CEILINGS AND MVFR TO IFR
VISIBILITIES IN RAIN AND FOG INTO FRIDAY MORNING. NORTHERLY GUSTS
DEVELOPING IN THE AFTERNOON.

KEWR FCSTER COMMENTS: VARIABLE CEILINGS AND VISIBILITIES IN SHOWERS
AND THUNDERSTORMS THROUGH 03Z...THEN IFR CEILINGS AND MVFR TO IFR
VISIBILITIES IN RAIN AND FOG INTO FRIDAY MORNING. NORTHERLY GUSTS
DEVELOPING IN THE AFTERNOON.

KTEB FCSTER COMMENTS: VARIABLE CEILINGS AND VISIBILITIES IN SHOWERS
AND THUNDERSTORMS THROUGH 03Z...THEN IFR CEILINGS AND MVFR TO IFR
VISIBILITIES IN RAIN AND FOG INTO FRIDAY MORNING. NORTHERLY GUSTS
DEVELOPING IN THE AFTERNOON.

KHPN FCSTER COMMENTS: VARIABLE CEILINGS AND VISIBILITIES IN SHOWERS
AND THUNDERSTORMS THROUGH 03Z...THEN IFR CEILINGS AND MVFR TO IFR
VISIBILITIES IN RAIN AND FOG INTO FRIDAY MORNING. NORTHERLY GUSTS
DEVELOPING IN THE AFTERNOON.

KISP FCSTER COMMENTS: MVFR VISIBILITIES IN SHOWERS AND FOG TONIGHT
WITH IFR TO LIFR CEILINGS. VISIBILITIES LOWER TO IFR LATE TONIGHT.
CONDITIONS IMPROVE TO MVFR MID TO LATE FRIDAY MORNING.

.OUTLOOK FOR 00Z SATURDAY THROUGH TUESDAY...
.FRIDAY NIGHT...NUMEROUS SHOWERS. MVFR TO IFR IN SHOWERS...FOG AND
STRATUS.
.SATURDAY...NUMEROUS SHOWERS WITH MVFR TO IFR. N WIND 25-30G35KT.
.SUNDAY...SCATTERED SHOWERS...IMPROVING CONDITIONS TO VFR. NW WIND
20-25KT. POTENTIAL FOR GUSTS UP TO 40KT.
.MONDAY THROUGH TUESDAY...VFR. NW WINDS 10-15G20KT ON MONDAY
BECOMING LIGHT AND VARIABLE ON TUESDAY.
-- End Changed Discussion --

&&

.MARINE...
SCA REMAINS UP FOR THE OCEAN WATERS THROUGH AT LEAST FRIDAY NIGHT
AS A LINGERING SWELL LIKELY KEEPS SEAS UP OVER 5 FT OVER A GOOD
PORTION OF THE OCEAN WATERS. GUSTS TO 25 KTS WILL BE POSSIBLE AS
WELL DURING PARTS OF THIS PERIOD ON THE OCEAN WATERS. NON-OCEAN
WATERS THROUGH FRIDAY SHOULD SEE GUSTS PEAK AT AROUND 20 KT...BUT
A FEW GUSTS TO 25 KT CANNOT BE COMPLETELY RULED OUT.

GUSTS IN STRENGTHENING N-NW FLOW ON THE BACK SIDE OF THE LOW AS IT
MOVES E OF NEW ENGLAND COULD REACH GALE FORCE SAT AFTERNOON/EVENING.
SCA CONDITIONS LIKELY TO CONTINUE ON ALL WATERS INTO SUNDAY
AFTERNOON...THEN GRADUALLY TAPER OFF ON THE OCEAN AND THEN ERN
SOUND/BAYS SUNDAY NIGHT. QUIET CONDITIONS EXPECTED MON-TUE VIA
BUILDING HIGH PRESSURE.

&&

.HYDROLOGY...
THERE IS THE POTENTIAL FOR AROUND AN ADDITIONAL 1-1.25 INCHES OF
RAINFALL WITH LOCALLY HIGHER AMOUNTS THROUGH FRIDAY MORNING.
PRECIPITABLE WATER VALUES OF AROUND 1.75 INCHES TONIGHT WILL ALLOW
FOR RAINFALL RATES TO APPROACH 2 INCHES AN HOUR IN STRONGER
CONVECTION. AS A RESULT EXPECT ADDITIONAL LOCALIZED FLASH FLOODING
FROM TONIGHT INTO FRIDAY MORNING. BECAUSE FORECAST BASIN AVERAGE
QPF DOES NOT EXCEED FLASH FLOOD GUIDANCE...AND ANY FLASH FLOODING IS
NOT EXPECTED TO BE WIDESPREAD...WILL NOT BE ISSUING A FLASH FLOOD
WATCH AT THIS TIME.

AN ADDITIONAL 1/2-3/4 OF INCH OF RAINFALL IS EXPECTED FROM FRIDAY
AFTERNOON THROUGH FRIDAY NIGHT - WITH LOCALLY HIGHER AMOUNTS
POSSIBLE. PRECIPITABLE WATERS DO DECREASE TO UNDER 1 INCH BY LATE
FRIDAY NIGHT. AS A RESULT...THE RISK OF MINOR URBAN FLOODING IN
THIS TIME FRAME WILL LIKELY BE RESTRICTED TO FRIDAY
AFTERNOON/EVENING...IF ANY OCCURS.

BASIN AVG QPF OF 1/2 TO 3/4 INCH EXPECTED SAT INTO SAT NIGHT...THEN
ONLY MINIMAL QPF IN LINGERING SHOWERS ON SUNDAY.

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...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ350-353-
     355.

&&

$$
SYNOPSIS...GOODMAN/MALOIT/NV
NEAR TERM...MALOIT/DW
SHORT TERM...MALOIT
LONG TERM...GOODMAN
AVIATION...MET
MARINE...GOODMAN/MALOIT
HYDROLOGY...GOODMAN/MALOIT/NV