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 212216
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
616 PM EDT TUE OCT 21 2014

.SYNOPSIS...
LOW PRESSURE DEVELOPS OVER THE DELMARVA AREA...AND THEN WILL
MEANDER SOUTH OF LONG ISLAND THROUGH MIDWEEK. THE LOW THEN TRACKS
NORTHEASTWARD INTO THE CANADIAN MARITIME PROVINCES LATE THIS WEEK
AND INTO THE WEEKEND. A COLD FRONT APPROACHES SATURDAY...THEN
CROSSES THE AREA SATURDAY NIGHT. HIGH PRESSURE BUILDS INTO THE MID
ATLANTIC STATES EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
GRIDS UPDATED TO ADJUST POPS ACROSS ERN LI WHERE WEAK TSTM COMPLEX
IS ROLLING THRU. TEMPS AND OTHER HOURLY FIELDS ADJUSTED. FCST
FOR SCT PCPN STILL LOOKS ON TRACK...HOWEVER SLOW MOVEMENT OF
ACTIVITY WILL RESULT IN POCKETS OF LINGERING PCPN...PARTICULARLY
OVER NJ AND THE LOWER HUDSON VALLEY.

DEEP UPPER LEVEL TROUGH AXIS APPROACHES TONIGHT AND MOVES TO JUST
WEST OF THE REGION WITH MID LEVEL CUTOFF LOW MOVING TOWARDS THE
DELMARVA. LOW AT THE SURFACE NEAR THE DELMARVA MOVES EAST AND
OFFSHORE BY WEDNESDAY MORNING.

BASICALLY...SCATTERED SHOWERS CONTINUE ACROSS THE REGION INTO THIS
EVENING WITH ISOLATED CONVECTION DUE TO STEEP LAPSE RATES. COULD
SEE SOME SMALL HAIL WITH ANY THUNDERSTORMS THAT FORM. WINDS ARE
STILL LIGHT OVERALL BUT BECOME MORE NORTHERLY LATE TONIGHT. LATE
TONIGHT...EXPECTING AN OVERALL INCREASE IN SHOWER COVERAGE WITH
ISOLATED THUNDERSTORMS STILL A POSSIBILITY AS MUCAPE VALUES STILL
COULD REACH 100-200 J/KG...CLOSER TO THE COAST.

LOWS WERE TAKEN FROM MAV GUIDANCE...WHICH IS RELATIVELY WARMER
THAN OTHER GUIDANCE...MID 40S TO MID 50S.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
LOW BECOMES NEARLY VERTICALLY STACKED BUT STILL RESULTS IN A
SLIGHT NEGATIVE TILT FOR CYCLOGENESIS TO OCCUR. THE LOW AT THE
SURFACE SOUTH OF LONG ISLAND GRADUALLY INTENSIFIES WEDNESDAY AND
WEDNESDAY NIGHT.

WITH COLD POOL ALOFT...RAIN WILL BE INCREASING ACROSS THE
REGION...ALTHOUGH INITIALLY IT LOOKS TO BE VERY LIGHT...PICKING UP
IN INTENSITY WEDNESDAY AFTERNOON THROUGH WEDNESDAY NIGHT.

PRESSURE GRADIENT INCREASES THROUGH THE PERIOD WITH A GUSTY
NORTHERLY FLOW DEVELOPING WEDNESDAY AND WEDNESDAY NIGHT.

RAIN MAY BECOME INTERMITTENT AT TIMES WITH DRY INTERVALS. MODELS
ARE HAVING DIFFICULTY PINPOINTING WHERE THE MORE CONSISTENT RAIN
WILL OCCUR.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
STACKED LOW EAST OF LONG ISLAND THU MORNING WILL BE SLOW TO LIFT
N/NE UP INTO THE CANADIAN MARITIMES THROUGH THE WEEKEND. ADDITIONAL
SHORT WAVE ENERGY WILL THEN FEED INTO THE MEAN TROUGH OVER EASTERN
NOAM SENDING A WEAK COLD FRONT ACROSS THE REGION SAT NIGHT.
THEREAFTER... THERE ARE SIGNS THAT A MORE PROGRESSIVE PATTERN WILL
ENSUE WITH THE FORECAST FOR A NEUTRAL NAO AND PNA.

RAIN WILL LINGER ON THE BACKSIDE OF THE COASTAL LOW THU INTO THU
NIGHT BEFORE CONDITIONS DRY OUT. GLOBAL MODELS HAVE TRENDED SLOWER
WITH THE CLEARING WITH CLOUD COVER POSSIBLY REMAINING THROUGH SAT.
HOWEVER...HAVE AIRED MORE OPTIMISTICALLY WITH CLEARING LATE FRI INTO
FRI NIGHT. AS FOR THE COLD FRONTAL PASSAGE SAT NIGHT...HAVE
MAINTAINED A DRY FRONTAL PASSAGE. THE 12Z ECMWF AND GFS DO HAVE SOME
LIGHT QPF. PREFER TO SEE MORE RUN TO RUN CONTINUITY BEFORE ADDING
ANY SHOWERS TO THE FORECAST. HIGH PRESSURE THEN BUILDS IN FROM SUN
NIGHT INTO MON...FOLLOWED BY A COLD FRONT APPROACHING FROM THE
MIDWEST ON TUE.

THROUGHOUT THE PERIOD...GUSTY W-NW WINDS WILL PREVAIL WITH THE
STRONGEST GUSTS LOOKING TO BE ON SUN BEHIND THE COLD FRONTAL
PASSAGE.

TEMPS WILL MODERATE FROM BELOW NORMAL ON THU WITH THE RAIN AND CLOUD
COVER TO ABOVE NORMAL EARLY NEXT WEEK AS A WARM RIDGE BUILDS IN
ALOFT AHEAD OF THE NEXT FRONTAL SYSTEM.

&&

.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
LOW PRESSURE REMAINS IN THE VICINITY INTO WEDNESDAY.

MOSTLY VFR INTO THIS EVENING. TIMING OF MVFR CEILINGS AND
PREVAILING -SHRA COULD BE OFF BY A FEW HOURS. SHRA/TSTMS COULD
PASS THROUGH AT ANY TERMINAL AT ANY GIVEN TIME INTO THIS
EVENING...BUT ANY TSTM ACTIVITY TOO SPARSE TO INCLUDE IN TAFS.
EXCEPTION IS KISP WHERE HAVE EVIDENCE OF CELL CURRENTLY CLOSE
ENOUGH TO WARRANT VCTS THROUGH 23Z.

ESE-SE WINDS AROUND 10KT...BACKING TO NE THIS EVENING. COULD BE A FEW
GUSTS 15-20KT THIS AFTERNOON. NE WINDS LIKELY GUSTING TO 20-25KT
WEDNESDAY.

     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: A PERIOD OF LIGHT AND VARIABLE WINDS OF 1-2
HOURS COULD PRECEDE THE WIND SHIFT TO NE. WINDS COULD SHIFT NE A
FEW HOURS EARLIER THAN FORECAST.

KLGA FCSTER COMMENTS: A PERIOD OF LIGHT AND VARIABLE WINDS OF 1-2
HOURS COULD PRECEDE THE WIND SHIFT TO NE. WINDS COULD SHIFT NE A
FEW HOURS EARLIER THAN FORECAST.

KEWR FCSTER COMMENTS: A PERIOD OF LIGHT AND VARIABLE WINDS OF 1-2
HOURS COULD PRECEDE THE WIND SHIFT TO NE. WINDS COULD SHIFT NE A
FEW HOURS EARLIER THAN FORECAST.

KTEB FCSTER COMMENTS: A PERIOD OF LIGHT AND VARIABLE WINDS OF 1-2
HOURS COULD PRECEDE THE WIND SHIFT TO NE. WINDS COULD SHIFT NE A
FEW HOURS EARLIER THAN FORECAST. TEMPO CIGS 2000-3000 FT POSSIBLE
UNTIL 23Z.

KHPN FCSTER COMMENTS: A PERIOD OF LIGHT AND VARIABLE WINDS OF 1-2
HOURS COULD PRECEDE THE WIND SHIFT TO NE. WINDS COULD SHIFT NE A
FEW HOURS EARLIER THAN FORECAST. -SHRA COULD PREVAIL FOR A TIME
LATE THIS AFTERNOON.

KISP FCSTER COMMENTS: A PERIOD OF LIGHT AND VARIABLE WINDS OF 1-2
HOURS COULD PRECEDE THE WIND SHIFT TO NE. WINDS COULD SHIFT NE A
FEW HOURS EARLIER THAN FORECAST. VCTS POSSIBLE UNTIL 23Z.

.OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
.WEDNESDAY AFTERNOON THROUGH THURSDAY NIGHT...MVFR OR LOWER CONDITIONS
IN SHRA. N-NW WINDS G25KT LIKELY AND G30KT POSSIBLE.
.FRIIDAY-FRIDAY NIGHT...MOST LIKELY VFR...WITH LOW CHANCE SPOTTY
MVFR. NW WINDS G20-25KT POSSIBLE.
.SATURDAY-SATURDAY NIGHT...VFR. NW-W WINDS G25-30KT POSSIBLE.
.SUNDAY...MAINLY VFR. NW WINDS G20-25KT POSSIBLE.

&&

.MARINE...
WINDS LIGHT AND FROM THE E-SE WITH SUB SCA CONDITIONS THROUGH
TONIGHT. WEAK PRESSURE GRADIENT PRESENT WITH LOW PRESSURE DEVELOPING
SOUTH OF THE WATERS. THE PRESSURE GRADIENT TIGHTENS ON WED THROUGH
WED NIGHT WITH LOW FURTHER DEEPENING. SCA CONDITIONS LIKELY BY
WED AFTERNOON ON ALL WATERS. SEAS INCREASE TO 5 TO 6 FT ON THE
COASTAL OCEAN WATERS WED AND WED NIGHT. THE HIGHER OCEAN SEAS
CONTINUE INTO THU. SCA FOR OCEAN WED THROUGH THU AND OTHER WATERS
WED AFTERNOON THROUGH WED NIGHT.

A PROLONGED PERIOD OF SCA CONDITIONS ARE FORECAST ON THE OCEAN
WATERS AS LOW PRESSURE EAST OF NEW ENGLAND THU LIFTS SLOWLY NE AND
UP INTO THE CANADIAN MARITIMES BY THIS WEEKEND. AT THE SAME
TIME...HIGH PRESSURE WILL SLOWLY WORK EAST AND INTO THE WATERS BY
EARLY NEXT WEEK. THIS WILL RESULT IN A GUSTY W-NW FLOW. MARGINAL
SCA GUSTS ARE POSSIBLE ON THE SOUND...HARBOR...AND SURROUNDING BAYS.

&&

.HYDROLOGY...
A FEW SHOWERS...AND POSSIBLY A THUNDERSTORM...WILL RESULT IN LESS
THAN A QUARTER OF AN INCH ON AVERAGE THROUGH TONIGHT. RAIN
INCREASES LATE TONIGHT THROUGH WEDNESDAY...WITH AROUND 1/2 QPF
FORECAST. LOCALIZED NUISANCE URBAN OR POOR DRAINAGE FLOODING IS
POSSIBLE.

PERIODS OF RAIN...BRIEFLY HEAVY IN SPOTS...COULD RESULT IN
LOCALIZED NUISANCE URBAN OR POOR DRAINAGE FLOODING WED THROUGH
THU.

STORM TOTALS SHOULD AVERAGE BETWEEN 1 AND 2 INCHES PER ANALYSIS OF
OPERATIONAL MODELS...AND SREF MEMBERS. THERE COULD BE SOME LOCALLY
HIGHER AMOUNTS. THIS AMOUNT OF RAIN SHOULD NOT RESULT IN ANY
SERIOUS LIFE THREATENING OR PROPERTY FLOODING ISSUES/CONCERNS.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON WEDNESDAY TO 6 AM EDT THURSDAY
     FOR ANZ330-335-338-340-345.
     SMALL CRAFT ADVISORY FROM 6 AM WEDNESDAY TO 6 PM EDT THURSDAY
     FOR ANZ350-353-355.

&&

$$
SYNOPSIS...JM
NEAR TERM...JMC/JM
SHORT TERM...JM
LONG TERM...DW
AVIATION...JC/MALOIT
MARINE...JM/DW
HYDROLOGY...JM/DW







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