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Area Forecast Discussion
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000
FXUS61 KOKX 190916
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
516 AM EDT FRI SEP 19 2014

.SYNOPSIS...
CANADIAN HIGH PRESSURE SLIDES EAST THROUGH NEW ENGLAND TODAY AND 
THEN OFF THE NORTHEAST COAST TONIGHT INTO SATURDAY. LOW PRESSURE
WILL TRACK ACROSS SOUTHEAST CANADA SATURDAY NIGHT AND
SUNDAY...DRAGGING A COLD FRONT ACROSS THE AREA SUNDAY NIGHT.
MEANWHILE...ANOTHER AREA OF LOW PRESSURE OFF THE SOUTHEAST COAST
WILL TRACK NORTHWARD...PASSING SOUTHEAST OF THE AREA. HIGH
PRESSURE BUILDS BACK IN FOR MONDAY AND REMAINS IN CONTROL THROUGH
THE END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INTENSE SHORTWAVE MOVES THROUGH NORTHERN NEW ENGLAND EARLY THIS 
MORNING WITH WEAKER ENERGY PASSING THROUGH THE AREA THROUGH THE 
MORNING. UPPER FLOW FLATTENS LATE IN THE DAY. 

GUSTY NE WINDS IN WAKE OF COLD FRONTAL PASSAGE WITH GLANCING SHOT OF 
CAA IN IT WAKE. WINDS GRADUALLY VEER TO THE E THROUGH THE DAY AS 
CANADIAN HIGH PRESSURE SLIDES THROUGH NEW ENGLAND.

MOISTURE TRAPPED UNDER POST-FRONTAL INVERSION RESULTING IN STRATO-CU 
DECK EARLY THIS MORNING. THIS STRATUS DECK SHOULD CONTINUE TO SINK 
SOUTH THROUGH THE MORNING...BUT GRADUALLY ERODE THROUGH THE MORNING 
AS DRIER AIR ADVECTS IN. SCATTERED INSTABILITY CLOUDS LIKELY RETURN 
THIS AFTERNOON ACROSS INTERIOR WITH DEVELOPING RETURN FLOW AND 
STRONG SUBSIDENCE INVERSION.

TEMPS WILL RUN A GOOD 10 OR SO DEGREES BELOW NORMAL UNDER FRESH 
CANADIAN AIRMASS WITH HIGH TEMPS IN THE 60S AREAWIDE...EVEN SOME 
UPPER 50S INTERIOR.

THERE IS GENERALLY A MODERATE RISK OF RIP CURRENTS AT ATLANTIC
OCEAN FACING BEACHES TODAY. NE WINDS AND ENE WIND WAVES WILL
PROMOTE A STRONG LONGSHORE CURRENT AND MODERATE RIP RISK. ONE
NOTE...EAST FACING SHORELINES AND THE EAST SIDE OF FIXED
STRUCTURES WILL SEE A HIGH RISK OF RIP CURRENTS...BUT OVERALL THIS
IS A LOCALIZED THREAT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
ZONAL UPPER FLOW EARLY...GIVE WAY TO EAST COAST RIDGING AS NORTHERN 
STREAM DIGS INTO THE GREAT LAKES.

AT THE SURFACE...CANADIAN HIGH PRESSURE CONTINUES TO SLIDE WELL 
OFFSHORE WITH RETURN FLOW DEVELOPING.

STRATUS DEVELOPMENT POSSIBLE LATE TONIGHT...PARTICULARLY ACROSS NYC 
METRO AND POINT W/NW...WITH RETURN FLOW TRAPPING MOISTURE UNDER 
SUBSIDENCE INVERSION. WITH POTENTIAL FOR CLOUD COVER AND ONSHORE 
FLOW TEMPS LIKELY DONT BOTTOM OUT...BUT STILL RUN SEVERAL DEGREES 
BELOW SEASONABLE. TEMPS IN THE 50S ALONG THE COAST...AND 40S 
INTERIOR.

GUSTY SE WAA FLOW ON SATURDAY WHICH SHOULD ALLOW FOR A MODERATION IN 
T/TD. MODELS SIGNALING SOME LIGHT PRECIP DEVELOPING IN RETURN 
FLOW...BUT WITH RATHER DRY SOUNDINGS AND LACK OF FORCING THIS MAY 
INDICATE POTENTIAL FOR STRATUS TO LINGER INTO THE AFTERNOON UNDER A 
LIFTING BUT LINGERING SUBSIDENCE INVERSION. TEMPS MODERATING TO NEAR 
SEASONABLE LEVELS WITH NOTICEABLE INCREASE IN HUMIDITY BY LATE DAY.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
MODEL GUIDANCE IS IN GOOD AGREEMENT WITH THE H5 FLOW THROUGH THE 
WEEKEND. TIMING AND AMPLITUDE DIFFERENCES THEN COME INTO PLAY 
THEREAFTER. ONE OTHER ELEMENT THAT BEARS WATCHING IS HOW QUICKLY THE 
DEVELOPING LOW OFF THE SE COAST IS PICKED UP BY THE DIGGING TROUGH. 
THERE SEEMS TO BE LARGE DISAGREEMENT WITH THIS LEADING TO HIGH 
VARIABILITY IN THE SYSTEMS FORWARD SPEED AND TRACK. SINCE THERE IS 
SUCH HIGH SPREAD AMONGST THE GUIDANCE WON'T GO INTO MUCH DETAILS AT 
THIS POINT...BUT POPS MIGHT NEED TO BE INCREASED SAT NIGHT INTO SUN 
AHEAD OF THE COLD FRONT AS MOISTURE STREAMS IN FROM THIS SYSTEM. IT 
COULD ALSO REMAIN FAR ENOUGH OFFSHORE KEEPING ALL PCPN THERE AS 
WELL. HAVE ADDED SCHC POPS FROM AREAS E OF FAIRFIELD COUNTY CT AND 
NASSAU COUNTY N NY FOR NOW AS GUIDANCE HAS BEEN INDICATING THIS AT 
TIMES OVER THE LAST FEW DAYS.

OTHERWISE...THE DIGGING TROUGH SLOWS UP OVER THE EAST COAST DUE TO 
DOWNSTREAM RIDGING...BUT STILL IS PROGRESSIVE ENOUGH FOR THE SFC 
COLD FRONT TO PUSH E OF THE AREA SUN NIGHT. DECENT SHORTWAVE 
ACCOMPANIES THE FRONT ALOFT...BUT IT SHOULD BE A FAIRLY QUICK SHOT 
OF RAIN WITH A SOMEWHAT MOISTURE STARVED ATMOSPHERE. THE NAM HAS 
BEEN DISCOUNTED AS IT IS THE ONLY SOLN THAT DEVELOPS A WAVE IN SRN 
NEW ENGLAND AND IS A SLOW OUTLIER WITH THE WAVE OFF THE SE COAST. 
THE SHORTWAVE ALSO PIVOTS INTO NEW ENGLAND DURING THE EVE TAKING THE 
BEST DYNAMICS WITH IT. HIGHEST CHCS OF PCPN WILL BE WEST OF THE 
HUDSON RIVER. HAVE ALSO ADDED SCHC TSTMS SUN AFTN/NIGHT WITH 
MARGINAL INSTABILITY POSSIBLE. HIGHS SUN ARE EXPECTED TO BE SEVERAL 
DEGREES ABOVE NORMAL WITH INCREASING HUMIDITY LEVELS.

THE FRONT IS EXPECTED TO CLEAR THE AREA BY MON MORNING...FOLLOWED BY 
THE TROF AXIS MON EVE. DEEP LAYERED RIDGING THEN BUILDS FROM THE 
PLAINS RESULTING IN DRY AND SEASONABLE WEATHER THROUGH THE REMAINDER 
OF THE WEEK.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE OVER EASTERN CANADA BUILDS SE AND OFF THE NEW
ENGLAND COAST BY THIS EVENING. 

THIS WILL RESULT IN NLY WINDS VEERING AROUND TO THE E/SE BY LATE
THIS AFT/EVE. SOME EARLY GUSTS UP TO 20 KT POSSIBLE THROUGH 15Z.

FORECAST DILEMMA HINGES ON THE DEVELOPMENT OF A STRATUS DECK
AROUND 3-4 KFT. PREFERENCE IS TO HOLD OFF AT THIS TIME DUE TO DRY
LOW LEVELS. THIS MAY BECOME MORE OF A FACTOR TONIGHT. THERE IS
SOME GUIDANCE THOUGH WHICH DEVELOPS THESE CLOUDS AS EARLY AS THIS
MORNING.

...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: POSSIBLE MVFR/VFR CIG...MAINLY AFT/EVE
HOURS.

KLGA FCSTER COMMENTS: POSSIBLE MVFR/VFR CIG...MAINLY AFT/EVE
HOURS.

KEWR FCSTER COMMENTS: POSSIBLE MVFR/VFR CIG...MAINLY AFT/EVE
HOURS.

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

KTEB FCSTER COMMENTS: POSSIBLE MVFR/VFR CIG...MAINLY AFT/EVE
HOURS.

KHPN FCSTER COMMENTS: POSSIBLE MVFR/VFR CIG...MAINLY AFT/EVE
HOURS.

KISP FCSTER COMMENTS: POSSIBLE MVFR/VFR CIG...MAINLY AFT/EVE
HOURS.

.OUTLOOK FOR 06Z SATURDAY THROUGH TUESDAY...
.SATURDAY-SUNDAY...POSSIBLE MVFR CONDITIONS EACH MORNING IN 
FOG/CLOUDS...IMPROVING TO VFR BY 15Z.
.SUNDAY NIGHT-MONDAY...CHANCE OF MVFR OR BELOW WITH SCATTERED
SHOWERS. G20-25 KT MON. 
.MONDAY NIGHT-TUESDAY...VFR.

&&

.MARINE...
MARGINAL NE SCA WINDS THIS MORNING SHOULD HAVE SEAS BUILD TO AROUND 
5 FT ACROSS OUTER WATERS. AS THE CENTER OF THE HIGH MOVES OFF THE 
NORTHEAST COAST THIS AFTERNOON WINDS EXPECTED TO VEER TO MORE 
EASTERLY DIRECTION AND WEAKEN A BIT. MARGINAL 5 FT SEAS LIKELY TO 
CONTINUE AS FETCH BECOMES MORE FAVORABLE. 

WINDS CONTINUE TO VEER TO SE TONIGHT INTO FRIDAY. SUB SCA WINDS AND 
DIMINISHING RESIDUAL E SWELLS FROM EDOUARD SHOULD ALLOW SEAS TO FALL 
JUST BELOW SCA. 

WINDS ARE EXPECTED TO REMAIN BELOW SCA LEVELS SAT NIGHT INTO MID
WEEK. SEAS ON THE OCEAN WATERS MAY BUILD TO MARGINAL SCA LEVELS
BEHIND A COLD FRONT SUN NIGHT INTO MON. SUB-ADVSY CONDS ARE THEN
EXPECTED UNTIL LATE TUE NIGHT INTO WED WITH AN INCREASING NLY
FLOW. SCA SEAS ON THE OCEAN ARE AGAIN POSSIBLE.

&&

.HYDROLOGY...
NO RAINFALL IS EXPECTED THROUGH SUNDAY.

LESS THAN 1/2 INCH OF RAINFALL IS EXPECTED WITH THE COLD FRONTAL 
PASSAGE SUN NIGHT. DRY WEATHER THEN EXPECTED FOR THE REST OF THE 
WEEK.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ350-
     353-355.

&&

$$

SYNOPSIS...24/NV
NEAR TERM...NV
SHORT TERM...NV
LONG TERM...24
AVIATION...DW
MARINE...24/NV
HYDROLOGY...24/NV






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