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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 181824
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
224 PM EDT SAT MAY 18 2013

.SYNOPSIS...
HIGH PRESSURE WILL SLIDE EAST OF THE AREA TODAY AND MOVE FURTHER
OUT TO SEA TONIGHT. A WARM FRONT WILL APPROACH FROM THE MID ATLANTIC
STATES SUNDAY INTO SUNDAY NIGHT AND THEN PASS TO THE NORTH ON
MONDAY. THE FRONT THEN REMAINS IN CLOSE PROXIMITY TO THE AREA
THROUGH THE WEEK UNTIL A COLD FRONTAL PASSAGE OCCURS LATE IN THE
WEEK OR EARLY WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST GENERALLY ON TRACK AS CLOUDS CONTINUE TO SLOWLY INCREASE
ACROSS THE NORTHEAST PORTION OF THE CWA...AND SKIES REMAIN CLOUDY
ELSEWHERE. IN ADDITION...SOME LIGHT RAIN SHOWERS HAVE BEEN
DEVELOPING ALONG THE NY/PA BORDER AND ARE HEADED TOWARD THE CWA.
HAVE INCLUDED SLIGHT CHANCE POPS...MAINLY ACROSS NJ...THE LOWER
HUDSON VALLEY AND NYC. WILL LIMIT THE POPS TO JUST 20 FOR
NOW.

OTHERWISE...HIGHS WILL BE IN THE UPPER 60S TO NEAR 70.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
THE HIGH MOVES FURTHER OFFSHORE TONIGHT WITH CLOUD COVER GRADUALLY
INCREASING FROM SW TO NE. STRATUS MAY DEVELOP LATE TONIGHT BUT
STILL EXPECT DRY CONDS.

A WARM FRONT WILL APPROACH SUN AND SUN NIGHT FROM THE SW.
INCREASING CLOUD COVER AND LATE DAY SHOWER ACTIVITY ARE EXPECTED
IN THIS WAA PATTERN. THE CONTINUATION OF THE INCREASINGLY MOIST SE
FLOW INTO SUN NIGHT POINTS TOWARDS CLOUDY CONDITIONS WITH LIGHT
RAIN...PATCHY DRIZZLE AND AREAS OF FOG DEVELOPING.

MODELS IN DECENT AGREEMENT WITH A WEAK SHORTWAVE APPROACHING SUN
NIGHT INTO MONDAY...WITH A WARM FRONTAL PASSAGE ON MONDAY...AND
REGION WARM SECTORED INTO TUESDAY. LOOKS LIKE THE FRONT MOVES
THROUGH IN THE MORNING...AND WITH THE SURGE OF A MORE UNSTABLE AIR
MASS THUNDERSTORMS ARE POSSIBLE WITH ITS PASSAGE. THE POTENTIAL
FOR SCATTERED AFTERNOON CONVECTION ALSO EXISTS BUT THERE IS
UNCERTAINTY IN HOW MUCH CLEARING THERE WILL BE IN THE AFTN. IT IS
STILL TOO EARLY TO DISCUSS SEVERE WEATHER OR FLOOD POTENTIAL WITH
THIS ACTIVITY WITH UNCERTAINTY ON MAGNITUDE OF INSTABILITY AND
FORCING.

TEMPERATURES ON SUNDAY WILL BE SLIGHTLY BELOW NORMAL DUE TO CLOUD
COVER...OTHERWISE...THEY WILL BE NEAR NORMAL LEVELS.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THERE ARE STILL SOME DISCREPANCIES AMONGST THE GLOBAL MODELS WITH
THE MAGNITUDE OF UPPER TROUGHING ACROSS EASTERN CANADA AS AN UPPER
RIDGE OVER THE MISSISSIPPI VALLEY TRANSLATES EAST THROUGH THE
UPCOMING WEEK. THE INTERACTION OF THE EASTERN CANADA TROUGHING AND
CENTRAL US TROUGHING WILL DETERMINE THE MAGNITUDE OF EAST COAST
RIDGING FOR THE MIDWEEK. MODELS ARE THEN SIGNALING A RETURN TO EAST
COAST TROUGHING FOR THE WEEKEND AS EAST COAST RIDGING BUILDS
OFFSHORE INTO THE WESTERN ATLANTIC.

ON TUESDAY...MODELS ARE IN GOOD AGREEMENT WITH AN UNSEASONABLY
WARM AND HUMID AIR MASS WORKING INTO THE REGION. DEPENDING ON THE
LOCATION OF THE FRONTAL BOUNDARY...FAVORABLE INSTABILITY AND WIND
FIELDS PRESENT THE POTENTIAL FOR SOME STRONG TO SEVERE CONVECTION
AHEAD/ALONG THIS BOUNDARY. LOCATION OF THE BOUNDARY WILL BE KEY.

THEN FOR THE MID-LATE WEEK PERIOD THE INTERACTION OF THE EARLIER
MENTIONED UPPER FEATURES WILL BE CRITICAL TO THE LOCATION OF THE
FRONTAL BOUNDARY AND WHETHER THE REGION REMAINS UNDER AN
UNSEASONABLY WARM AND UNSTABLE AIR MASS WED-FRI...OR WHETHER THE
PICTURE IS MORE MUDDLED WITH A FRONTAL BOUNDARY MEANDERING ACROSS
THE REGION FOR MUCH OF THE TIME PERIOD WITH CLOUDS AND SEASONABLE TO
SLIGHTLY BELOW SEASONABLE TEMPS.

REGARDLESS OF WHERE THE WARM FRONT ENDS UP...IF THIS BOUNDARY REMAIN
CLOSE TO THE REGION...SHORT WAVES AT THE SOUTHERN EDGE OF THE
WESTERLIES MAY ALLOW FOR CONVECTIVE COMPLEXES TO FORM AND TRACK WEST
TO EAST ALONG THIS BOUNDARY THROUGH THE MIDWEEK PERIOD. THESE WOULD
BRING THE THREAT FOR HEAVY RAIN AND SEVERE WEATHER...BUT IT IS TOO
FAR OUT DISCUSS SPECIFICS.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
HIGH PRESSURE WILL MOVE TO THE EAST THROUGH THE PERIOD WHILE A
WARM FRONT SLOWLY APPROACHES FROM THE SOUTH.

BAND OF LIGHT RAIN/SPRINKLES WAS MOVING INTO THE NYC METRO AREA AS
OF 18Z. CONDS SHOULD BE MOSTLY VFR WITH THIS BAND...BUT CANNOT
RULE OUT BRIEF MVFR VSBY AT THE START AT KTEB/KLGA.

S FLOW 10 KT OR LESS SHOULD DIMINISH TONIGHT AND THEN BACK SE AS
THE HIGH PULLS OFF TO THE EAST AND THE WARM FRONT GETS A LITTLE
CLOSER. LIGHT RAIN WITH MVFR CIGS LIKELY TO ARRIVE TO THE NYC
METRO TERMINALS...POSSIBLY AS EARLY AS 05Z-06Z BUT MORE LIKELY
CLOSER TO DAYBREAK SUNDAY. IFR CONDS LIKELY BY AFTERNOON.
KGON WILL BE THE EXCEPTION TO THE RULE HERE...WITH MVFR CONDS
THROUGH THE END OF THE PERIOD.

.OUTLOOK FOR 18Z SUNDAY THROUGH WED...

.SUNDAY AFTERNOON/NIGHT...MVFR OR LOWER CONDS EXPECTED IN LIGHT
RAIN AS WARM FRONT APPROACHES AND STALLS JUST TO THE SOUTH AT
NIGHT. SE SFC WIND 10-15 KT...DIMINISHING AT NIGHT.

.MON...WARM FROPA...WITH IMPROVEMENT TO VFR BY MID TO LATE
MORNING. SCT SHOWERS WITH BRIEF MVFR CONDS POSSIBLE IN
THE AFTERNOON.

.MON NIGHT...MVFR OR LOWER CONDS LIKELY WITH LOW CLOUDS AND FOG.

.TUE-WED...CHANCE OF MVFR OF LOWER CONDS IN SHOWERS/TSTMS WITH
STATIONARY FRONTAL BOUNDARY NEARBY OR JUST TO THE SOUTH.

.THU...WARM FROPA WITH IMPROVEMENT TO VFR DURING THE MORNING...
THEN COLD FROPA WITH LATE DAY/NIGHTTIME SHOWERS/TSTMS.
-- End Changed Discussion --

&&

.MARINE...
HIGH PRESSURE PASSES TO THE EAST OF THE WATERS...RESULTING IN A
SOUTHERLY FLOW THIS WEEKEND. SMALL CRAFT ADVISORY THRESHOLDS ARE NOT
EXPECTED UNTIL POSSIBLY SUNDAY NIGHT OR MONDAY AS WINDS INCREASE AND
OCEAN SEAS BUILD DUE TO THE PERSISTENT SOUTHERLY FETCH.

A WARM FRONT MOVES NORTH OF THE WATERS MONDAY...AND SHOULD REMAIN TO
THE NORTH THROUGH TUESDAY. THE FRONT MAY SAG SOUTH AGAIN AND REMAIN
IN THE VICINITY OF THE WATERS THROUGH MID WEEK.

SOUTH TO SOUTHWEST WINDS PERSIST INTO TUESDAY. ONCE THE FRONT
SETTLES BACK TOWARD THE WATERS...WINDS LIGHTEN AND MAY
SHIFT...DEPENDING ON HOW FAR SOUTH THIS FRONT MOVES. STAY TUNED.

&&

.HYDROLOGY...
NO SIGNIFICANT RAINFALL IS EXPECTED THROUGH SUN NIGHT.

ALTHOUGH WIDESPREAD HEAVY RAIN EVENTS ARE NOT EXPECTED MON-
FRI...THUNDERSTORMS ARE POSSIBLE THROUGH THIS PERIOD...WHICH WOULD
BE CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL.

&&

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

&&

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