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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 191959 CCA
AFDOKX

AREA FORECAST DISCUSSION...CORRECTED SYNOPSIS
NATIONAL WEATHER SERVICE NEW YORK NY
354 PM EDT SUN MAY 19 2013

.SYNOPSIS...
-- Changed Discussion --
A WARM FRONT WILL SLOWLY APPROACH TONIGHT...THEN LIFT TO THE NORTH
MONDAY INTO MONDAY NIGHT. THIS FRONT WILL THEN REMAIN NEARBY THROUGH
MID WEEK...POSSIBLY SINKING SOUTH ON TUESDAY AND LIFTING BACK NORTH
AS A WARM FRONT ON WEDNESDAY. A COLD FRONTAL PASSAGE WILL OCCUR LATE
IN THE WEEK. HIGH PRESSURE WILL RETURN NEXT WEEKEND.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
-- Changed Discussion --
WEAK WAA STILL CAUSING LIGHT RAIN AND DRIZZLE TO CONTINUE ACROSS
MOST OF THE AREA LATE THIS AFTERNOON. UPDATED POP TO LIKELY/CAT FOR
MOST OF THE AREA PER RADAR TREND. THIS GENERAL SCENARIO SHOULD LAST
INTO THIS EVENING AS A DIFFUSE WARM FRONT TO THE SOUTH APPROACHES...
THEN POP SHOULD TAPER OFF AFTER MIDNIGHT FROM WEST TO EAST AS BEST
ISENTROPIC LIFT MOVES TO THE NE. TEMPS SHOULD REMAIN NEARLY STEADY
TONIGHT IN THE MID AND UPPER 50S...AND COULD SLOWLY INCREASE TOWARD
DAYBREAK. AS HIGHER DEWPOINT AIR ADVECTS IN...POTENTIAL FOR FOG WILL
ALSO INCREASE ESPECIALLY LATE TONIGHT.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
THE REGION WILL BE WARM SECTORED ON MONDAY. EXPECT AT LEAST
PARTIAL CLEARING TO OCCUR...WHICH WILL DETERMINE AMT OF DAYTIME
HEATING/INSTABILITY. FORCING RELATIVELY WEAK...SO EXPECT ONLY
ISOLD TO SCT SHOWERS IN THE AFTERNOON. WITH WEAK STEERING FLOW
AND PW NEAR 1.5 INCHES...ANY SHOWER/TSTM COULD DUMP LOCALLY HEAVY
RAIN. HIGH-RES MESOSCALE MODELS SUCH AS SPC WRF AND HIGH-RES ARW
AGREE ON THIS SCENARIO.

EXPECT DAYTIME HIGHS TO REACH THE LOWER 80S FROM NYC NORTH/WEST
AND INTO THE 70S ELSEWHERE. TEMPS COULD BE A COUPLE DEG HIGHER IF
MORE AFTERNOON SUNSHINE TAKES PLACE THAN FCST.

ANY CONVECTION SHOULD WANE MON EVENING. IT NOW APPEARS THAT A BACK
DOOR COLD FRONT APPROACHING FROM NEW ENGLAND SHOULD HOLD OFF UNTIL
TUE MORNING...SO WITH AREA REMAINING IN THE WARM SECTOR WOULD
EXPECT REDEVELOPMENT OF FOG...ESPECIALLY ALONG THE COAST.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
MEDIUM RANGE MODELS/ENSEMBLES ARE IN DECENT GENERAL AGREEMENT
WITH THE REGION LYING ON THE NORTHERN PERIPHERY OF EAST COAST
RIDGING DURING THE MIDWEEK...WITH PHASING EASTERN CANADIAN AND
CENTRAL US TROUGHS...EVENTUALLY TRANSLATING A DEEP TROUGH TO THE
EAST COAST FOR THE END OF THE WEEK/WEEKEND.

FOR TUESDAY THROUGH THURSDAY...MODELS CONTINUE TO DIFFER IN LOCATION
OF A FRONTAL BOUNDARY. THE PREDICTABILITY ISSUES ARE BASED ON
SUBTLE DIFFERENCES IN INTERACTION OF THE UPPER ENERGIES AND
RELATIONSHIP WITH EAST COAST RIDGING. THE LOCATION OF UPPER
CONFLUENCE WILL DETERMINE HOW STRONGLY CANADIAN HIGH PRESSURE BUILDS
SE INTO NEW ENGLAND...AND THE TIMING AND MOVEMENT OF A BACK DOOR
COLD FRONT. LATEST GUIDANCE PUSHES THE BACKDOOR COLD FRONT SOUTH
THROUGH THE REGION ON TUESDAY...AND THEN BACK NORTH AS A WARM FRONT
ON WEDNESDAY.

TO THE SOUTH OF THE FRONT...AN UNSEASONABLY WARM AND MOIST AIR MASS
WILL BE IN PLACE. DEPENDING ON THE TIMING AND LOCATION OF THE
FRONTAL BOUNDARY...SHORTWAVES AT THE SOUTHERN EDGE OF THE
WESTERLIES...FAVORABLE INSTABILITY AND WIND FIELDS PRESENT THE
POTENTIAL FOR CONVECTIVE COMPLEXES TO DEVELOP AND PROPAGATE ALONG
THIS BOUNDARY. ANY MCS WOULD BRING THE THREAT FOR FLASH FLOODING AND
SEVERE WEATHER.

BY THE END OF THE WEEK...MODELS ARE SIGNALING VARYING DEGREES OF
PHASING OF THE MIDWEST UPPER TROUGH AND EASTERN CANADIAN UPPER
TROUGH. MODELS HAVE TRENDED FASTER WITH THIS PHASED ENERGY WORKING
TO THE EAST COAST. HAVE TRENDED COLD FRONTAL PASSAGE A BIT SOONER AS
A RESULT...SOME TIME LATE THU THROUGH FRI...WITH SHOWER AND
THUNDERSTORM ACTIVITY FINALLY EXITING IN IT WAKE. DEGREE OF PHASING
OF UPPER ENERGIES WILL DETERMINE TIMING AND ACTIVITY ALONG THE FRONT.

MODEL GUIDANCE IS SIGNALING A DRIER AND SLIGHTLY BELOW SEASONABLE
WEEKEND...WITH EAST COAST MEAN TROUGHING AND CANADIAN HIGH PRESSURE
BUILDS INTO THE REGION.
-- End Changed Discussion --

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
A FRONTAL BOUNDARY APPROACHES FROM THE SOUTH TODAY AND TONIGHT.

SUB VFR THROUGH MUCH OF THE FORECAST. CONDITIONS HAVE FALLEN TO
MVFR-IFR THIS AFTERNOON AND ARE EXPECTED TO REMAIN DOWN THROUGH
TONIGHT AS A WARM FRONT APPROACHES FROM THE SOUTH. LITTLE TO NO
IMPROVEMENT IS EXPECTED...ESPECIALLY ALONG THE COASTAL
TERMINALS...AND IF ANY IMPROVEMENT DOES OCCUR...IT WONT LAST VERY
LONG.

CONDITIONS TONIGHT CONTINUE TO FALL TO IFR OR LESS AT ALL THE AREA
TERMINALS. THE LOW STRATUS WILL BE OVER THE REGION LOWERING CIGS TO
ANYWHERE FROM 200-1000 FT. QUESTION IS HOW MUCH FOG DEVELOPS. WILL
LIMIT VSBY RESTRICTIONS TO JUST 2 MILES FOR NOW...HOWEVER VSBYS
COULD FALL TO LESS THAN A MILE IN SPOTS.

WINDS WILL REMAIN FROM THE SOUTHEAST TODAY...THEN BECOME LIGHT AND
VARIABLE OVERNIGHT. TOMORROW...WINDS BECOME SOUTH OR SOUTHWEST AND
REMAIN LESS THAN 10 KT.

.OUTLOOK FOR 18Z MONDAY THROUGH THURSDAY...

.MON...IMPROVEMENT TO VFR BY LATE MORNING OR EARLY AFTERNOON.
SCATTERED SHOWERS/ISOLATED TSTMS WITH BRIEF MVFR CONDITIONS
POSSIBLE IN THE AFTERNOON.

.MON NIGHT...MVFR OR LOWER CONDITIONS LIKELY...WITH
LOW CLOUDS/FOG.

.TUE-THU...CHANCE OF MVFR OF LOWER CONDITIONS IN SHOWERS/TSTMS.

.FRI...CHANCE OF MVFR IN ANY LEFTOVER SHOWERS/TSTMS EARLY.

&&

.MARINE...
AS HIGH PRESSURE PASSES TO THE EAST AND A WARM FRONT APPROACHES
FROM THE SOUTH...SE-S WINDS SHOULD INCREASE TO 15 TO 20
KT...MAINLY ACROSS THE OCEAN WATERS. OCEAN SEAS STILL 2-4
FT...SHOULD REACH SCA CRITERIA OF 5 FT THIS EVENING...SO PUSHED
START TIME OF OCEAN SCA FORWARD A LITTLE MORE TO 6 PM. SCA LEVEL
OCEAN SEAS SHOULD LAST INTO MON AFTERNOON...POSSIBLY INTO MON
EVENING OUT EAST.

WITH EXPECTATION OF A FRONTAL BOUNDARY TO BE MEANDERING ACROSS THE
REGION DURING THE MID WEEK PERIOD...SUB SCA WINDS ARE EXPECTED.
WILL HAVE TO MONITOR MAGNITUDE OF SOUTHERLY SWELLS THROUGH MID
WEEK...BUT SEAS SHOULD LIKELY REMAIN BELOW SCA WITH WEAK FLOW.
A STRENGTHENING S-SW FLOW ON THU COULD BUILD OCEAN SEAS TO SCA...
PARTICULARLY OUT EAST. HAVE UNDERCUT WAVEWATCH BY 1-2 FT DURING
THIS TIME PERIOD DUE TO THE USUAL WARM SEASON BIAS.

COLD FRONTAL PASSAGE SOMETIME THU NIGHT INTO FRI...WITH WIND SHIFT
TO THE NW BEHIND IT. A GRADUAL SUBSIDING OF SOUTHERLY SWELLS WOULD
BE EXPECTED BEHIND THE FRONT.

&&

.HYDROLOGY...
UP TO 1/4 INCH QPF EXPECTED THROUGH TONIGHT. SCT SHOWERS/TSTMS MON
THROUGH FRI ARE CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL...WITH
AN ATTENDANT LOW END FLASH FLOOD THREAT.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 AM EDT MONDAY FOR ANZ355.
     SMALL CRAFT ADVISORY UNTIL 6 PM EDT MONDAY FOR ANZ350-353.

&&

$$

SYNOPSIS...GOODMAN/NV
NEAR TERM...GOODMAN
SHORT TERM...GOODMAN
LONG TERM...NV
AVIATION...BC
MARINE...GOODMAN/NV
HYDROLOGY...GOODMAN/NV