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Area Forecast Discussion
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000
FXUS61 KOKX 311437
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1037 AM EDT SUN AUG 31 2014

.SYNOPSIS...
LOW PRESSURE TRACKING ACROSS EASTERN CANADA WILL SEND A TROUGH
ACROSS THE AREA LATE THIS AFTERNOON INTO THIS EVENING. ANOTHER
TROUGH WILL THEN WORK ACROSS THE AREA MONDAY AFTERNOON AND
EVENING. WEAK HIGH PRESSURE BRIEFLY BUILDS IN MONDAY NIGHT INTO
TUESDAY MORNING. A COLD FRONT WILL THEN MOVE THROUGH TUESDAY
NIGHT WITH HIGH PRESSURE BUILDING IN FROM THE SOUTH AND WEST
THROUGH THURSDAY. THE HIGH MOVES OFFSHORE FRIDAY WITH ANOTHER COLD
FRONT APPROACHING INTO THE BEGINNING OF NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATED FORECAST TO DELAY ONSET OF SHOWER CHANCES UNTIL THIS
AFTN...ALTHOUGH AN ISOLATED SHOWER COULD POP UP BEFORE NOON. ALSO
INTRODUCED PARTIAL SUNSHINE TO SOME OF THE SOUTHERN FRINGE OF THE
AREA AS PER SATELLITE TRENDS. REST OF THE FORECAST PRETTY MUCH ON
TRACK. 

A SIGNIFICANT CHANGE IN THE WEATHER THE LAST 24H AS THE UPPER
RIDGE AXIS HAS PASSED TO THE EAST WITH AN INFLUX OF TROPICAL
MOISTURE FROM THE GULF COAST STATES. LATEST WATER VAPOR IMAGERY
SHOWS THE MOISTURE TRANSPORT FROM THE WESTERN GULF OF MEXICO WITH
MULTIPLE SHORT WAVES EMBEDDED IN THE FLOW. THESE LATER TODAY WILL
INTERACT WITH A SFC TROF TO PRODUCE WIDESPREAD CONVECTION ACROSS THE
NORTHERN MID ATLANTIC AND SOUTHERN NEW ENGLAND STATES. 

THE PRIMARY THREAT LOOKS TO BE LOCALIZED HEAVY RAINFALL LATE THIS
AFTERNOON TO THE WEST OF NYC...THEN OVERSPREADING THE REST OF THE
TRI-STATE AREA THIS EVENING. PW IN EXCESS OF 2 INCHES...MLCAPES OF
1000-1500 J/KG...AND 30-40 KT OF DEEP-LAYERED SHEAR SUPPORTS
ORGANIZED CONVECTION WITH POSSIBLE LINE SEGMENTS AND
STRONG/DAMAGING WINDS. THERE IS STILL SOME CONCERN FOR THE
BOUNDARY TO LAY DOWN OR BECOME NEARLY STATIONARY EAST OF
NYC...WITH THE POSSIBILITY OF TRAINING OF CELLS. THE 00Z MODEL
GUIDANCE HAS THOUGH SHOWN MORE PROGRESSION SINCE THE PREVIOUS 
00Z MODEL SUITE.

IN ADDITION...VERY WARM...MUGGY CONDITIONS WILL PREVAIL WITH HIGHS
IN THE LOW TO MID 80S AND DEW POINTS AROUND 70. MIGHT NEED TO BUMP
UP HIGHS OVER SOME OF THE SOUTHERN ZONES IF CLOUDS DO NOT FILL
BACK IN AS QUICKLY AS ANTICIPATED. OVERNIGHT LOWS WILL HAVE A
TOUGH TIME GETTING TOO FAR BELOW THE 70 DEGREE MARK WITH CLOUD
COVER AND AN ONSHORE FLOW.

A MODERATE RISK OF RIP CURRENTS IS EXPECTED TODAY AT THE ATLANTIC
FACING BEACHES...BUT THIS MAY INCREASE TO HIGH BY LATE IN THE DAY
WITH INCREASING SOUTHERLY WINDS.

&&

.SHORT TERM /MONDAY/...
POTENTIAL EXISTS FOR ANOTHER ROUND OF STRONG AFT/EVE CONVECTION
ON MON AS ANOTHER TROF SETS UP JUST WEST OF THE AREA AND THEN
APPROACHES BY EARLY EVE. THIS TIME AROUND THOUGH WINDS ALOFT ARE
NOT AS FAVORABLE FOR ORGANIZED CONVECTION. HOWEVER...MLCAPES OF
1000-1500 J/KG COUPLED WITH PW AROUND 2 INCHES WILL KEEP
LOCALIZED HEAVY RAINFALL A THREAT.

HIGHS MON ARE FORECAST TO BE A TOUCH WARMER WITH DEW POINTS
REMAINING AROUND 70.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
THE DOMINANT PATTERN IN THE LONG TERM IS THAT OF RIDGING ON AVERAGE. 
ON A LARGE SCALE...AN UPPER LEVEL RIDGE IS APPARENT ON THE MODEL
HEIGHT FIELDS ALOFT FROM QUEBEC TO THE MID-ATLANTIC. A RELATIVELY
STRONGER UPPER LEVEL TROUGH PASSES NORTH OF THE REGION LATE
TUESDAY INTO EARLY WEDNESDAY WITH SOME MORE HEIGHT FALLS AND A
TRANSITION TO ZONAL FLOW. RIDGING RESUMES THEREAFTER WITH THE
LARGE RIDGE ACROSS THE SOUTHERN U.S. PUSHING NORTH FROM WEDNESDAY
THROUGH FRIDAY.

AT THE SURFACE...A SURFACE TROUGH MOVING IN FROM THE WEST
DISSIPATES WITHIN THE REGION WITHOUT MUCH UPPER LEVEL SUPPORT ON
MONDAY. A WEAK PRESSURE GRADIENT IS LEFT IN ITS PLACE WITHOUT A
STRONG PRESENCE OF HIGH PRESSURE. THE JET STREAM WILL BE LIFTING
NORTH AWAY FROM THE REGION HELPING EXPLAIN THE LACK OF SUPPORT
ALOFT. THE JET PUSHES BACK SOUTH TUESDAY NIGHT INTO EARLY
WEDNESDAY...SO THIS WILL HELP PUSH A COLD FRONT THROUGH THE
REGION. THIS WILL TRANSITION WINDS TO MORE OF A NORTHERLY FLOW FOR 
WEDNESDAY. THE FLOW WEAKENS THURSDAY...ALLOWING FOR SEA BREEZES
TO DEVELOP AS HIGH PRESSURE BUILDS IN FROM THE SOUTH AND WEST. THE
HIGH MOVES OFFSHORE FRIDAY INTO THE NEXT WEEKEND. ANOTHER COLD FRONT
APPROACHES INTO THE BEGINNING OF NEXT WEEKEND.

OUTSIDE OF WEDNESDAY...A GENERAL SOUTH TO SOUTHWEST FLOW DOMINATES 
NEXT WEEK. THIS WILL RESULT IN TEMPERATURES WELL ABOVE SEASONAL 
AVERAGES FOR THIS TIME OF YEAR. THE JET STREAM OVERALL KEEPS TO THE 
NORTH OF THE REGION. TEMPERATURES WILL BE GENERALLY 5-10 DEGREES
ABOVE NORMAL MONDAY THROUGH WEDNESDAY AND A FEW DEGREES ABOVE
NORMAL WEDNESDAY NIGHT THROUGH SATURDAY.

ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS FROM NORTHWEST TO
SOUTHEAST TUESDAY INTO TUESDAY NIGHT WITH A LITTLE MORE SHEAR TO
WORK WITH. MAINLY DRY THEREAFTER WITH A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS TOWARDS END OF THE WORK WEEK INTO THE NEXT
WEEKEND WITH NEXT FRONT APPROACHING.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A TROUGH OF LOW PRES APPROACHES FROM THE WEST THIS AFTERNOON AND 
MOVES ACROSS THE AREA TONIGHT. 

MVFR CIGS ARE EXPECTED TO LIFT TO VFR THIS AFTERNOON. HZ MAY DEVELOP 
THIS AFTERNOON AND COULD LOCALLY RESTRICT VSBY TO MVFR IN SPOTS. 
SOUTH TO SW WINDS EXPECTED TODAY...AND A FEW GUSTS 15 TO 20 KTS ARE 
POSSIBLE...ESPECIALLY CSTL AND NYC METRO AIRPORTS.

ISOLATED SHRA/TSRA POSSIBLE ALONG SEA BREEZE BOUNDARIES THIS AFTN
BUT CHCS ARE TOO LOW TO INCLUDE. OTHERWISE...INCREASING CHANCE
FOR SHRA/TSTMS LATE AFTN/EVE MAINLY FROM CITY TERMINALS AND POINTS 
N/W AS TROUGH APPROACHES. TIMING OF CONVECTION MAY NEED TO BE 
ADJUSTED A FEW HOURS. THESE INCREASING CHCS TRANSLATE EWD DURING THE 
EVE. MVFR TO LOCALLY IFR POSSIBLE IN CONVECTION. UNCERTAINTY IN HOW 
PROGRESSIVE RAIN IS ACROSS THE AREA AND MAY BE HOLDING ON TO IT TOO 
LONG.

MVFR CONDS POSSIBLE AGAIN LATE TONIGHT INTO MON MORNING WITH A
MOIST AIRMASS REMAINING IN PLACE...ESPECIALLY WHERE PCPN ENDS AND
LIGHT WINDS DEVELOP.

.OUTLOOK FOR 12Z MON THROUGH THU...
.MON-MON NIGHT...ADDITIONAL SCT SHRA/TSRA POSSIBLE MON AFT/EVE.
MVFR STRATUS/FOG POSSIBLE LATE MON NIGHT.
.TUE...SCT AFT/EVE SHRA/TSRA POSSIBLE. 
.WED-THU...MAINLY VFR.

&&

.MARINE...
THE PRES GRADIENT WILL TIGHTEN TODAY AS LOW PRES PASSES TO THE N AND 
HIGH PRES CONTINUES TO DEPART OUT TO SEA. THIS WILL RESULT IN AN 
INCREASING SLY FLOW. SEAS ON THE OCEAN WATERS WILL BUILD IN
RESPONSE WITH SCA CONDS EXPECTED TO BE MET THIS EVENING AND
CONTINUE THROUGH THE NIGHT BEFORE SUBSIDING EARLY MON MORNING.
THERE IS THE POTENTIAL FOR 5 FT SEAS TO LINGER A FEW HOURS LONGER
E OF MORICHES INLET...BUT WILL END THE HAZARD AT 10Z FOR NOW. WIND
GUSTS WILL ALSO COME CLOSE TO 25 KT AT TIMES...MAINLY THIS EVE.

SUB-ADVSY CONDS ARE THEN EXPECTED THROUGH THE REMAINDER OF THE 
FORECAST PERIOD WITH A FAIRLY WEAK GRADIENT OVER THE AREA.

&&

.HYDROLOGY...
DEEP MOISTURE IN PLACE WITH A SERIES OF SHORTWAVES ALOFT AND
SURFACE TROUGHS WILL INTERACT TO PRODUCE CONVECTION EACH 
AFT/EVE OVER THE NEXT COUPLE OF DAYS WITH THE POTENTIAL FOR
LOCALIZED HEAVY RAINFALL. A LOCALIZED FLOOD THREAT REMAINS FOR
FLASH FLOODING. ON AVERAGE...LOOKING FOR ABOUT AN INCH OF
RAINFALL ACROSS THE BASINS...WITH SEVERAL INCHES POSSIBLE IN
STRONGER MORE ORGANIZED CONVECTION.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EDT MONDAY 
     FOR ANZ350-353-355.

&&

$$
SYNOPSIS...DW
NEAR TERM...JC/DW
SHORT TERM...DW
LONG TERM...JM/DW
AVIATION...24/PW
MARINE...24
HYDROLOGY...DW






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