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Area Forecast Discussion
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000
FXUS61 KOKX 220233
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1033 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/...
UPPER LOW CURRENTLY OVER WESTERN PA. THIS WILL DROP SOUTHEASTWARD
AND HELP TO DEEPEN A SFC LOW OFF THE DELMARVA. AT THE SAME
TIME...A 1030S HI OVER QUEBEC WILL CONTINUE TO EASE TOWARDS THE
MARITIMES. AS A RESULT...LOW LEVEL FLOW IS ALREADY BACKING TO THE
N ACROSS THE CWA...AND THIS WILL CONTINUE.

THE STABLE FLOW WILL REDUCE TSTM CHANCES FOR THE REMAINDER OF THE
NIGHT. THEY MAY BE REMOVED WITH THE NEXT UPDATE. DID REMOVE THE
HAIL HOWEVER AS MLCAPE DECREASES.

WITH THE NORTHERLY FLOW...IT MAY BE DIFFICULT TO DEVELOP
SIGNIFICANT FOG. MAINTAINED PATCHY BUT INCREASED VSBY.

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 /02Z WEDNESDAY THROUGH SUNDAY/...
LOW PRESSURE REMAINS SOUTH OF LONG ISLAND INTO WEDNESDAY EVENING.

MAINLY VFR...WITH A FEW POCKETS OF MVFR EARLY OVERNIGHT. THEN
MVFR DEVELOPS THROUGHOUT LATE OVERNIGHT AND CONTINUES THROUGH THE
REMAINDER OF THE TAF PERIOD. SMALL CHANCE OF POCKETS OF IFR EARLY
WEDNESDAY MORNING WITH AREA OF -RA MOVING THROUGH MAINLY
WESTERN/CITY TERMINALS FROM AROUND 8 TO 14/15Z. CONFIDENCE IN LOCATION
AND OCCURRENCE OF ANY IFR CONDITIONS TO LOW TO PLACE IN ANY TAF.

PRECIPITATION WEDNESDAY...AFTER AFOREMENTIONED -RA THROUGH
14/15Z...WILL BE RATHER SPOTTY. IT WILL NOT BE RAINING
CONTINUOUSLY...AND PROBABLY WILL NOT RAIN AT LEAST HALF THE TIME
IN ANY GIVEN HOUR...SO WENT WITH VCSH FOR NOW. WILL REFINE LATER
WHEN TIMING OF PRECIPITATION BECOMES MORE APPARENT.

WINDS BECOME NE-NNE THROUGHOUT OVERNIGHT...INCREASE TO AROUND 10KT
LATE TONIGHT...THEN BECOME GUSTY WEDNESDAY WITH GUSTS UP TO
20-25KT BY MID MORNING AT ALL BUT KSWF...WHERE THE GUSTS SHOULD
HOLD OFF UNTIL AFTERNOON.

.OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...
.WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...MVFR OR LOWER CONDITIONS IN
SHRA. N-NW WINDS G25-30KT LIKELY.
.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 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...MALOIT
MARINE...JM/DW
HYDROLOGY...JM/DW








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