Area Forecast Discussion
Issued by NWS Upton, NY

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000
FXUS61 KOKX 191047
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
647 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 THIS MORNING WITH
GLANCING SHOT OF CAA IN IT WAKE. WINDS GRADUALLY VEER TO THE E
THIS AFTERNOON AND WEAKEN A BIT AS CANADIAN HIGH PRESSURE SLIDES
THROUGH NEW ENGLAND.

MOISTURE TRAPPED UNDER POST-FRONTAL INVERSION RESULTING IN SCT-BKN
STRATO- CU DECK EARLY THIS MORNING. THIS STRATUS DECK SHOULD
CONTINUE TO SINK SOUTH THROUGH THE MORNING...AND 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. EAST
FACING SHORELINES AND THE EAST SIDE OF FIXED STRUCTURES WILL SEE
AN ENHANCED RISK OF RIP CURRENTS...BUT OVERALL THIS WOULD 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 /12Z 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 WILL HAVE SEAS CONTINUE TO BUILD
TO 4 TO 6 FT ACROSS OCEAN WATERS. AS THE CENTER OF THE HIGH MOVES
OFF THE NORTHEAST COAST THIS AFTERNOON WINDS EXPECTED TO VEER TO
A 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 MIDNIGHT EDT TONIGHT 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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