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698
FXUS61 KOKX 021443
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1043 AM EDT TUE SEP 2 2014

.SYNOPSIS...
A COLD FRONT APPROACHES FROM THE WEST THIS AFTERNOON...THEN
CROSSES THE TRI-STATE TONIGHT. WEAK HIGH PRESSURE BUILDS IN ON
WEDNESDAY...THEN REMAINS OVER THE REGION INTO FRIDAY. A COLD FRONT
WILL APPROACH FRIDAY NIGHT AND MOVE ACROSS THE REGION SATURDAY AND
SATURDAY NIGHT. HIGH PRESSURE RETURNS FOR THE START OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FOG HAS DISSIPATED ACROSS MUCH OF THE AREA WITH THE EXCEPTION OF
A FEW PATCHES ALONG THE COAST NEAR SE CT AND THE SOUTH FORK NEAR
MONTAUK. VERY HIGH DEW POINT AIR...70 TO 75...TRAVERSING THE
COOLER NEAR SHORE WATERS HAS ALLOWED FOR THIS FOG. THIS THOUGH
SHOULD NOT LAST MUCH LONGER DUE TO DAYTIME HEATING AND SLIGHTLY
LOWER DEW POINTS BY AFT.

OTHERWISE...CONVECTIVE FORECAST FOR TODAY IS A CHALLENGING ONE.
WHILE A PRE-FRONTAL TROUGH WILL DEVELOP AND REMAIN OVER MAINLY
WESTERN/NORTHERN ZONES...APPEARS SHOULD HAVE A WEAK CAP DEVELOP
AROUND 650 HPA. SO EVEN WITH 1500-2500 J/KG OF CAPE FORECAST...THE
WEAK CAP COUPLED WITH BEST DYNAMIC FORCING PROGGED TO OUR N...AND
RELATIVELY WEAK SHEAR 20 KT OR LESS UNTIL MAYBE VERY LATE IN THE
DAY OVER FAR W ZONES AS LOW-MID LEVEL JET APPROACHES THERE.
APPEARS BEST CHANCE FOR ANY CONVECTION IS OVER AREAS N/W OF NYC
LATE THIS AFTERNOON WITH ARRIVAL OF LOW-MID LEVEL JET.

GIVEN ABOVE...FEEL THAT MOST LIKELY CAP HOLDS ON OVER THE SE 2/3
OF THE CWA...SO HAVE GONE WITH A DRY FORECAST THERE. HAVE CHANCE
POPS BY LATE AFTERNOON OVER MAINLY ORANGE AND PUTNAM COUNTIES AND
SLIGHT CHANCE POPS IN BETWEEN. ANY CONVECTION THAT DOES FORM WILL
BE MAINLY OF THE PULSE VARIETY...WITH SOME MULTI-CELLULAR
STRUCTURES POSSIBLE BY LATE AFTERNOON OVER MAINLY ORANGE COUNTY
WITH ARRIVAL OF LOW-MID LEVEL JETS. BASED ON THIS FEEL SEVERE
THREAT IS MINIMAL THIS AFTERNOON...BUT CANNOT BE COMPLETELY RULED
OUT.

HIGH REMAIN ON TRACK FOR THE UPPER 80S TO LOWER 90S WITH HEAT
INDICES APPROACHING 100 IN METRO NY.

THERE IS A MODERATE RISK OF RIP CURRENT FORMATION AT ATLANTIC
BEACHES TODAY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
REGION WILL BE IN THE RIGHT REAR QUADRANT OF 80-90 KT 300 HPA
JET...PASSING OF STRENGTHENING LOW-MID LEVEL JETS IN THE
EVENING...AND THE AREA UNDER DIFFLUENT FLOW IN THE MID
LEVELS...COUPLED WITH PRECIPITABLE WATERS FORECAST TO INCREASE TO
AROUND 2 INCHES...THEN HAVE THE POTENTIAL FOR LOCALLY HEAVY
RAINFALL IN ANY STORMS THAT DO FORM THIS EVENING. REFER TO HYDROLOGY
SECTION OF THE AFD FOR FURTHER DETAILS.

HOWEVER...WILL BE WORKING AGAINST DIMINISH CAPE WITH THE LOSS OF
SOLAR HEATING...WITH BEST DYNAMICS PASSING TO THE N...BELIEVE THAT
ANY SEVERE POTENTIAL RAPIDLY DIMINISHES DURING THE EARLY EVENING
HOURS...AND IT WAS NOT ALL THAT HIGH TO BEGIN WITH.

700-500 HPA SHORTWAVES LIFTS TO THE N/E OF THE AREA TONIGHT...WITH
ZONAL FLOW DEVELOPING WEDNESDAY...ALLOWING FOR THINGS TO DRY OUT
LATE TONIGHT BEHIND THE SHORTWAVES.

FOR LOWS TONIGHT...USED A BLEND OF MAV/MET GUIDANCE WITH NAM
2-METER TEMPERATURES...WITH VALUES FORECAST TO BE AROUND 5 DEGREES
ABOVE NORMAL. FOR HIGHS WEDNESDAY USED A BLEND OF MIXING DOWN FROM
850-825 HPA PER BUFKIT SOUNDINGS...WITH NAM 2-METER TEMPERATURES
AND A BLEND OF MAV/MET GUIDANCE. THIS YIELDS HIGHS AROUND 5-10
DEGREES ABOVE NORMAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE OVER THE REGION WEDNESDAY NIGHT THROUGH FRIDAY WILL
KEEP CONDITIONS SUNNY AND DRY. AS THE HIGH MOVES OFFSHORE ON
THURSDAY...EXPECT HUMIDITY LEVELS TO INCREASE THURSDAY NIGHT AND
FRIDAY.

A COLD FRONT WILL APPROACH THE AREA FRIDAY NIGHT INTO
SATURDAY...PUSHING OFFSHORE SOMETIME SATURDAY NIGHT. EXPECT SHOWERS
AND THUNDERSTORMS TO ACCOMPANY THE FRONT. MOST OF THE MODELS ARE IN
GOOD AGREEMENT ON THE TIMING OF THE FRONT. HOWEVER...A FEW OF THE
MODELS WANT TO LINGER SOME PRECIPITATION INTO SUNDAY BEHIND THE
FRONT. FOR NOW...DO NOT WANT TO RULE THIS OUT...SO WILL KEEP SOME
CHANCE/SLIGHT CHANCE POPS IN FOR NOW.

HIGH PRESSURE OVER CANADA WILL BUILD SOUTH BEHIND THE COLD
FRONT...BRINGING COOLER AND LESS HUMID CONDITIONS TO THE REGION FOR
THE START OF NEXT WEEK.

TEMPERATURES THURSDAY THROUGH SATURDAY WILL REMAIN ABOVE NORMAL WITH
HIGHS IN THE MIDDLE TO UPPER 80S. SLIGHTLY COOLER CONDITIONS CAN BE
EXPECTED RIGHT ALONG THE COASTAL SECTIONS.  TEMPERATURES THEN FALL
BELOW NORMAL SUNDAY THROUGH TUESDAY WITH HIGHS ONLY IN THE 70S.

&&

.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT APPROACHES TODAY AND PASSES THROUGH TONIGHT.

VFR. ISO/SCT TSTMS WITH BRIEF SUB-VFR CONDS THIS AFTN AND
EVENING...POSSIBLY AS EARLY AS AROUND 19Z...BUT MORE LIKELY TO OCCUR
AFTER 00-01Z. NOT ENOUGH CONFIDENCE IN COVERAGE AND PLACEMENT TO
INCLUDE IN TAFS.

     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: SEA BREEZE SHIFT COULD BE AROUND AN HOUR OFF
IN EITHER DIRECTION.

KLGA FCSTER COMMENTS: SEA BREEZE COULD POTENTIALLY SHIFT WINDS TO
THE SOUTH AROUND 21Z. NOT ENOUGH CONFIDENCE TO INCLUDE THIS SHIFT
YET.

KEWR FCSTER COMMENTS: OCNL GUSTS 15-18 KT.

THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.

KTEB FCSTER COMMENTS: ANY AMENDMENTS MOST LIKELY RELATED TO TSTM
POTENTIAL.

KHPN FCSTER COMMENTS: ANY AMENDMENTS MOST LIKELY RELATED TO TSTM
POTENTIAL.

KISP FCSTER COMMENTS: ANY AMENDMENTS MOST LIKELY RELATED TO TSTM
POTENTIAL.

.OUTLOOK FOR 12Z WED THROUGH FRI...
.WED-FRI NIGHT...VFR.
.SAT...SUB-VFR PSBL IN SCT SHRA/TSRA.

&&

.MARINE...
WINDS WILL BE 15 KT OR LESS ON THE WATERS THROUGH WEDNESDAY.
THERE IS SOME POTENTIAL THAT SEAS COULD BUILD TO 5 FT ON ANZ-350
TONIGHT...WITH TIGHTENING OF PRESSURE GRADIENT AHEAD OF THE
FRONT...AND RESIDUAL 1-2 FT SWELLS. HOWEVER CONFIDENCE IN THIS IS
NOT ALL THAT HIGH...SO DO NOT REFLECT IN FORECAST AT THIS TIME.
SEAS SHOULD COME DOWN ON WEDNESDAY WITH A WEAKENING PRESSURE
GRADIENT OVER THE AREA.

GENERALLY LOOKING AT SUB-SCA CONDITIONS ON THE AREA WATERS WEDNESDAY
NIGHT THROUGH THE WEEKEND. A COLD FRONT WILL PUSH ACROSS THE WATERS
SATURDAY NIGHT INTO SUNDAY...WHICH WILL RESULT IN HIGHER WINDS AND
SEAS.

&&

.HYDROLOGY...
SPOTTY SHRA/TSTMS MAINLY OVER AREAS N/W OF NYC...COULD PRODUCE
ISOLATED LOCALLY HEAVY RAINFALL. AREAS EXPERIENCING LOCALLY HEAVY
RAINFALL COULD EXPERIENCE MINOR URBAN/POOR DRAINAGE FLOODING.
OUTSIDE OF AREAS EXPERIENCING LOCALLY HEAVY RAINFALL...LESS THAN
0.2 INCHES OF BASIN AVERAGE PRECIPITATION IS EXPECTED FROM ANY
PRECIPITATION THAT DOES FALL THIS AFTERNOON AND TONIGHT.

IT SHOULD THEN BE DRY FROM WEDNESDAY THROUGH AT LEAST FRIDAY.

&&

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

&&

$$

SYNOPSIS...BC/MALOIT
NEAR TERM...BC/MALOIT/DW
SHORT TERM...MALOIT
LONG TERM...BC
AVIATION...JC/SEARS
MARINE...BC/MALOIT
HYDROLOGY...BC/MALOIT







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