Area Forecast Discussion
Issued by NWS Upton, NY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KOKX 260832
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
432 AM EDT TUE MAY 26 2015

.SYNOPSIS...
THE BERMUDA HIGH REMAINS ANCHORED WELL OFF THE EASTERN SEABOARD
THROUGH WEDNESDAY. A WEAK COLD FRONT WILL APPROACH THE AREA
WEDNESDAY NIGHT...AND REACH THE TRI-STATE REGION THURSDAY. THE
FRONT WILL DISSIPATE OVER THE AREA ON FRIDAY. ANOTHER COLD FRONT
WILL APPROACH ON SATURDAY...AND SAG SOUTH OF THE REGION ON SUNDAY.
THE FRONT WILL THEN BECOME STATIONARY FOR THE BEGINNING OF NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REGION REMAINS ON N/W PERIPHERY OF DEEP LAYERED RIDGE. QUESTION IS
ARE NW ZONES FAR ENOUGH REMOVED FROM THE RIDGE TO GET ANY
DIURNALLY DRIVEN CONVECTION. THE GFS/NAM ARGUE YES...THE
CMC/ECMWF ARGUE NO.

NOTING FORECAST OF 500-1500 J/KG CAPE OVER NW ZONES ON AVERAGE (NO
CAPE IN ECMWF)...AND EVEN THE ECMWF HAVING A WEAK SHORTWAVE
PASSING TO THE N GOING OVER THE TOP OF THE RIDGE...HAVE CONTINUED
WITH MAINLY SLIGHT CHANCE POPS OVER NW ZONES...WITH CHANCE POPS W
ORANGE COUNTY.

FOR HIGHS TODAY USED A BLEND OF MAV/MET/ECS GUIDANCE WITH NAM
2-METER TEMPERATURES AND A MIX DOWN FROM 975 TO 850 HPA PER
BUFKIT SOUNDINGS. HIGHS SHOULD BE AROUND 10 DEGREES ABOVE NORMAL.

LIKE YESTERDAY...EXPECT A FAIRLY STRONG SEABREEZE TO PENETRATE
WELL INLAND THIS AFTERNOON...THOUGH PROBABLY NOT INTO ORANGE
COUNTY...BASED ON HIGH RESOLUTION MODELS. THE SEABREEZE BOUNDARY
COULD ALSO SERVE AS A TRIGGER FOR CONVECTION OVER NW INTERIOR
ZONES IF FORECAST CAPE IS REALIZED.

THERE IS A MODERATE RISK FOR METEOROLOGICAL ENHANCEMENT OF RIP
CURRENT DEVELOPMENT AT ATLANTIC OCEAN BEACHES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
CORE OF DEEP LAYERED RIDGE SLIDES SLIGHTLY FARTHER TO THE S/E
THROUGH WEDNESDAY.

FOR TONIGHT...THE CMC/ECMWF KEEP THINGS DRY...WITH NO FORCING.
WHILE THE GFS/NAM BRING A WEAK 700-500 HPA SHORTWAVE OVER MAINLY
N/W PORTIONS OF THE AREA. GIVEN UNCERTAINTY HAVE CAPPED POPS AT
SLIGHT CHANCE.

GIVEN PERSISTENT ONSHORE FLOW AND FORECAST DEVELOPMENT OF A LOW
LEVEL INVERSION...EXPECT FOR LOW CLOUDS TO DEVELOP
TONIGHT...TIMING IS SOMEWHAT UNCERTAIN...BUT WOULD EXPECT S SHORE
LOCATIONS TO GO FIRST...AFTER SUNSET...WITH INTERIOR AREAS
CLOUDING UP AROUND/AFTER MIDNIGHT. ANY LOW CLOUDS WILL BE LAST TO
REACH NW ZONES...IF THEY DO AT ALL...NOTING WEAKER IF NOT NON-
EXISTENT LOW LEVEL INVERSION IN BUFKIT SOUNDINGS AT KMGJ/KSWF. IN
ADDITION TO THE STRATUS...HAVE THE POTENTIAL FOR FOG AS WELL. IF
THE SHOWERS/TSTMS MATERIALIZE...WOULD NOT EXPECT ANY FOG UNTIL
AFTER THEY PASS. AS IS ALWAYS THE CASE WHEN YOU HAVE MARINE
INDUCED STRATUS...IS IT IS NEVER CERTAIN WHETHER YOU WILL GET FOG
AS WELL...SO RESTRICTED FOG TO PATCHY AND AT THIS TIME WILL NOT
FORECAST ANY LOCALLY DENSE FOG...THOUGH CANNOT RULE IT
OUT...ESPECIALLY NEAR THE IMMEDIATE COAST.

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

ON WEDNESDAY CONVECTIVE POTENTIAL OVER WESTERN ZONES WILL BE AIDED
BY FORMATION OF A LEE/THERMAL TROUGH...PASSING OF A 30-35 KT 950
HPA JET...AND MODEL AVERAGE FORECAST CAPES OF 1000-2000 J/KG.
BASED ON THIS HAVE 40-50 POPS OVER NW ZONES BY AFTERNOON...WITH
CHANCE POPS INTO NYC/SW CT AND SLIGHT CHANCE ELSEWHERE. AS IS
ALWAYS THE QUESTION THIS TIME OF YEAR...IS HOW LONG DO STORMS STAY
TOGETHER AS THEY HEAD EAST INTO THE MARINE LAYER. WITH BULK
RICHARDSON NUMBER GENERALLY FORECAST TO BE MUCH GREATER THAN
40...WOULD EXPECT MAINLY ISOLATED PULSE STORMS. HOWEVER...IF
THE HIGH END OF MODEL FORECAST CAPE IS REALIZED...THEN SOME
LOCALIZED SEVERE STORMS CANNOT BE COMPLETELY RULED OUT...WITH THE
BEST CHANCE OVER THE LOWER HUDSON VALLEY W OF THE HUDSON RIVER.

FOR HIGHS WEDNESDAY USED A BLEND OF MIXING DOWN FROM 975 TO 900
HPA PER BUFKIT SOUNDINGS WITH NAM 2-METER TEMPERATURES AND A BLEND
OF MAV/ECS/MET GUIDANCE. HIGHS SHOULD BE AROUND 5-10 DEGREES ABOVE
NORMAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
RESIDUAL CONVECTION IS LIKELY TO EASE THRU THE REGION WED NIGHT.
THE FRONT WILL STILL BE ACROSS UPSTATE NY AND CENTRAL PA AT THIS
POINT PER THE NAM AND GFS. A DECENT RIBBON OF CAPE AHEAD OF THE
FRONT ON THU. THIS INSTABILITY AXIS SHOULD RESIDE FROM ROUGHLY
NORTHEASTERN NJ THRU THE HUDSON VALLEY AND INTO WRN CT. THE
PERSISTENT SWLY SFC FLOW WILL KEEP THE COASTS FAIRLY STABLE. THE
CITY WILL BE IN THE GRADIENT REGION...WITH THE SEA BREEZE
INFLUENCE ATTEMPTING TO STABILIZE THE AREA AS WELL. THE FRONT WILL
BE A FOCUS FOR TSTMS PER THE 00Z GUIDANCE. HOWEVER...THE FRONT
LOOKS TO DISSIPATE AS IT ENCOUNTERS THE COOLER MARITIME INFLUENCED
AIRMASS. AS A RESULT THE BOUNDARY MAY NEVER EVEN MAKE IT TO ERN
AREAS. SLY FLOW DEVELOPS ON FRI AS THE PRES FALLS N OF THE REGION.
THIS FALLING PRES WILL BE ASSOCIATED WITH A STRONGER COLD
FRONT...WHICH WILL APPROACH ON SAT BEFORE STALLING S OF THE AREA
LATE SUN INTO TUE. GOOD CHANCES FOR CONVECTION SAT. PRECIPITATION TYPE
AND CHANCES WILL TIED TO THE POSITION OF THE FRONT SUN AND MON.
FOR NOW IT LOOKS LIKE THE FRONT WILL BE FAR ENOUGH S TO KEEP THE
CWA FIRMLY IN THE COLDER AIRMASS WITH EASTERLY WINDS AND RAIN
CHANCES AS OPPOSED TO SHOWERS AND TSTMS. HOWEVER...THIS IS STILL
FAR OUT AND EVEN A FRONTAL POSITION JUST S OF THE CWA COULD ALLOW
FOR ELEVATED CONVECTION.

&&

.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE REMAINS EAST OF THE AREA FOR THE NEXT SEVERAL DAYS.

VFR THROUGH MUCH OF THE TAF PERIOD. THERE IS A CHANCE OF
THUNDERSTORMS NORTH AND WEST OF NYC THIS AFTERNOON. WILL INCLUDE A
PROB30 GROUP FOR THIS AT KSWF. ANY THUNDERSTORMS COULD PRODUCE BRIEF
SUB-VFR CONDITIONS.

SOUTH TO SOUTHWEST WINDS INCREASE THIS MORNING TO 10 TO 15 KT AND BY
AFTERNOON WIND MAY BE 15 TO 20 KT SUSTAINED WITH GUSTS 20 TO 25 KT.
WINDS DIMINISH THIS EVENING.

...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: TIMING OF WIND GUSTS MAY BE OFF BY AN HOUR OR
TWO. PEAK WIND GUSTS MAY BE SLIGHTLY HIGHER THAN FORECAST.

KLGA FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY AN HOUR OR
TWO. PEAK WIND GUSTS MAY BE SLIGHTLY HIGHER THAN FORECAST.

KEWR FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY AN HOUR OR
TWO. PEAK WIND GUSTS MAY BE SLIGHTLY HIGHER THAN FORECAST.

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

KTEB FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY AN HOUR OR
TWO. PEAK WIND GUSTS MAY BE SLIGHTLY HIGHER THAN FORECAST.

KHPN FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY AN HOUR OR
TWO. PEAK WIND GUSTS MAY BE SLIGHTLY HIGHER THAN FORECAST.

KISP FCSTER COMMENTS: TIMING OF WIND GUSTS MAY BE OFF BY AN HOUR OR
TWO. PEAK WIND GUSTS MAY BE SLIGHTLY HIGHER THAN FORECAST.

.OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...
.TUESDAY NIGHT...THERE IS A LOW CHANCE OF SOME MVFR STRATUS ALONG
THE IMMEDIATE COAST OF LONG ISLAND.

.WEDNESDAY...LOW CHANCE OF EARLY MORNING MVFR  STRATUS. LOW CHANCE
OF AFTERNOON AND EARLY EVENING SHRA/TSTM...MAINLY NORTH AND WEST OF
THE NYC METRO TERMINALS. SOUTHERLY WIND GUSTS UP TO 25 KT.

.THURSDAY-SATURDAY...THIS IS A CHANCE OF LATE NIGHT AND EARLY
MORNING MVFR OR LOWER STRATUS AND/OR FOG. THERE IS A LOW CHANCE OF
AFTERNOON AND EVENING SHRA/TSTM. WIND GUSTS 20-25 KT.

&&

.MARINE...
HAVE CONTINUED WITH SCA ON THE COASTAL OCEAN WATERS THROUGH
TONIGHT...WITH GUSTS AGAIN THIS AFTERNOON TO AROUND 25 KT HELPING
TO KEEP SEAS AT AROUND 5 FT. HAVE ALSO ISSUED AN SCA FOR NY HARBOR
AND THE S SHORE BAYS OF LONG ISLAND FROM 16Z TODAY THROUGH 4Z
TONIGHT FOR GUSTS TO AROUND 25 KT WITH THE SEABREEZE. ON THE
REMAINDER OF THE WATERS FOR TODAY AND TONIGHT..EXPECT GUSTS TO TOP
OUT AT 20 KT THIS AFTERNOON/EVENING.

THERE IS THE POTENTIAL FOR AREAS OF DENSE FOG TO FORM OVER THE
WATERS LATE TONIGHT AND LINGER INTO WEDNESDAY MORNING...WHAT FORMS
COULD ALSO JUST END UP BEING AN AREA OF LOW CLOUDS. TO SOON TO
TELL...SO WENT WITH PATCHY FOG LOWERING VISIBILITIES TO 1-3NM.

FOR WINDS AND WAVES ON WEDNESDAY...ITS LIKELY WILL BE SIMILAR TO
YESTERDAY/TODAY WITH SCA SEAS ON THE COASTAL OCEAN WATERS ALL
DAY...AND GUSTS TO 25 KT ON THE COASTAL OCEAN ZONES/NY HARBOR/S
SHORE BAYS OF LONG ISLAND IN THE AFTERNOON. HOWEVER...CONFIDENCE
IS NOT QUITE HIGH ENOUGH TO EXTEND THE SCA INTO WEDNESDAY AT THIS
TIME.

SCA SEAS REMAIN ON THE OCEAN WED NIGHT THEN GRADUALLY SUBSIDE
THRU THE DAY ON THU. WINDS WILL BE MARGINAL ON THE OCEAN AND S
SHORE BAYS...AND BELOW SCA LEVELS ELSEWHERE. LIGHTER FLOW THU
THRU FRI NIGHT WITH CONDITIONS BELOW SCA LEVELS. WINDS AND SEAS
BUILD ON SAT AHEAD OF A COLD FRONT WITH SCA CONDITIONS POSSIBLE BY
SUNSET...ESPECIALLY THE OCEAN. AS THE FRONT STALLS S OF THE WATERS
SUN AND MON...NE FLOW WOULD DRIVE SEAS TO 5 FT OR MORE ON THE
OCEAN...WITH WIND SPEEDS IN THE 15-25KT RANGE ALL WATERS.

&&

.HYDROLOGY...
GENERALLY LESS THAN 1/10 OF AN INCH OF BASIN AVERAGE RAINFALL IS
EXPECTED THROUGH WEDNESDAY. HOWEVER ANY STRONGER CONVECTION THAT
FORMS...ESPECIALLY IF THERE IS ANY TRAINING OF STORMS...COULD
LEAD TO MINOR FLOODING OF URBAN AND/OR POOR DRAINAGE AREAS.

LOCALLY HEAVY RAINFALL IS POSSIBLE DURING THE FIRST HALF OF THE
WEEKEND AS A COLD FRONT IMPACTS THE AREA.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ350-353-
     355.
     SMALL CRAFT ADVISORY FROM NOON TODAY TO MIDNIGHT EDT TONIGHT
     FOR ANZ338-345.

&&

$$
SYNOPSIS...JMC/MALOIT
NEAR TERM...MALOIT
SHORT TERM...MALOIT
LONG TERM...JMC
AVIATION...BC
MARINE...JMC/MALOIT
HYDROLOGY...JMC/MALOIT


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.