Skip Navigation Linkswww.nws.noaa.gov 
NOAA logo - Click to go to the NOAA homepage National Weather Service Forecast Office   NWS logo - Click to go to the NWS homepage
Upton, NY banner image
 
 

Area Forecast Discussion
Latest Versions  [Current][-1][-2][-3][-4]



000
FXUS61 KOKX 200840
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
340 AM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE REGION THIS WEEKEND INTO MONDAY. A 
WAVE OF LOW PRESSURE WEAKENS AS IT APPROACHES MONDAY NIGHT INTO 
TUESDAY. A MORE SIGNIFICANT STORM SYSTEM THEN AFFECTS THE AREA 
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...WITH ITS EFFECTS STILL FELT 
ON THURSDAY. HIGH PRESSURE BUILDS IN ON FRIDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE TO THE NORTH SHIFTS EAST TOWARD MAINE. THE MAIN 
FORECAST CHALLENGE TODAY WILL BE THE AMOUNT OF CLOUD COVER. SOME 
MOISTURE IS BEING TRAPPED UNDER AN INVERSION NEAR 900MB...AND MODELS 
IN GENERAL AGREEMENT THAT MOISTURE INCREASES BELOW THIS DURING THE 
AFTERNOON. WILL GO WITH A PARTLY TO MOSTLY CLOUDY FORECAST. QPF 
OUTPUT ALSO INDICATES VERY LIGHT PCPN CHANCES OVER THE FORKS 
REGION/SE CT TOWARDS SUNSET...BUT WILL MAINTAIN A DRY FORECAST FOR 
THE DAYTIME. MAV/NAM MOS BLEND LOOKED GOOD FOR HIGH TEMPS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
WE WILL HAVE A CHANCE OF PCPN FOR SOME AREAS TONIGHT...BUT VERY 
LIGHT. DURING THE EVENING...WEAK LIFT...MAINLY OVER THE EASTERN 
AREAS...WILL BE SUPPLIED BY A SHORTWAVE IN THE LOW-MID LEVELS. THIS 
COMBINED WITH LOW LEVEL  MOISTURE IN PLACE WILL BRING A CHANCE OF 
FLURRIES OVER LONG ISLAND AND SE CT. THEN FOR THE OVERNIGHT 
HOURS...CHANCES OF FLURRIES SPREAD WEST WITH LOW LEVEL MOISTURE 
ADVECTION AND INCREASING PVA FROM THE WEST. THINKING IS THAT PCPN 
TYPE WOULD FAVOR FLURRIES OVER SPRINKLES IN SPITE OF MOISTURE 
LACKING IN THE MID LEVELS. LOOKS LIKE COLDEST TEMPS IN THE SATURATED 
LAYER BENEATH THE LOW LEVEL INVERSION WILL BE COLD ENOUGH TO SUPPORT 
ICE CRYSTALS. BOUNDARY LAYER TEMPS WOULD ALSO TEND TO FAVOR FLURRIES.

MID LEVEL SHORTWAVE PASSES THROUGH SUNDAY MORNING WITH 
FLURRIES/SPRINKLES...THEN NVA BEHIND IT AND DEEP-LAYERED RIDGING 
LIKELY PREVENTS PCPN IN THE AFTERNOON. HIGH TEMPS NEAR NORMAL. DRY 
WEATHER CONTINUES INTO SUNDAY NIGHT WITH HIGH PRESSURE RIDGING.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
WEAK LOW PRESSURE FORMS ALONG A FRONTAL BOUNDARY OFF THE CAROLINA 
COAST ON MONDAY AND BEGINS TO HEAD NORTH. MEANWHILE...HIGH PRESSURE 
CENTERED TO THE NORTHEAST SHIFTS FARTHER EAST. THIS WILL LOW LEVEL 
WINDS HERE VEER TO THE EAST AND AID LOW LEVEL MOISTURE ADVECTION. A 
SURFACE TROUGH EXTENDING NORTH FROM THE CENTER OF THE LOW WILL SERVE 
AS A FOCUS FOR WEAK LIFT AND MOISTURE CONVERGENCE. LOW CHANCES OF 
LIGHT RAIN RESULT...BUT BETTER OVERALL CHANCES OCCUR DURING THE 
AFTERNOON. 

THE LOW CENTER WEAKENS AS IT HEADS NORTH MONDAY NIGHT AND TUESDAY. 
HOWEVER... ISENTROPIC LIFT AHEAD OF THE LOW STILL STRENGTHENS...LOW 
LEVEL MOISTURE STILL INCREASES ON AN ENE FLOW...AND THE SURFACE 
TROUGH WILL STILL BE IN THE VICINITY. POPS FOR TUESDAY MIGHT BE A 
LITTLE TOO HIGH BUT THEY ARE STILL REASONABLE...AND CURRENTLY DO NOT 
HAVE THE CONFIDENCE TO LOWER POPS FROM THE CURRENT LOW-END LIKELY. 
BETTER OVERALL CHANCES OF RAIN OCCUR IN THE AFTERNOON. PCPN TYPE 
RAIN...EXCEPT A MIX OF RAIN AND SNOW LATE MON NIGHT AND TUES MORNING 
FOR THE NORTHERN FRINGE ZONES. MIGHT NEED TO MONITOR FOR THE 
POSSIBILITY OF MINOR COASTAL FLOODING STARTING WITH TUESDAY 
MORNING'S HIGH TIDE CYCLE AS A PERSISTENT EASTERLY FLOW STRENGTHENS.

A STRONGER STORM SYSTEM THEN AFFECTS US CHRISTMAS EVE AND DAY. 
MODELS SHOW A STRONG PRIMARY LOW CENTER MOVING THROUGH THE GREAT 
LAKES REGION ON WEDNESDAY BEFORE MOVING INTO ONTARIO ON THURSDAY. A 
WEAKER SECONDARY LOW PRESSURE CENTER OR TRIPLE POINT LOW FORMS IN 
THE MID ATLANTIC REGION BEFORE PASSING OVER OR JUST NORTH OF US 
WEDNESDAY NIGHT. THIS WILL DRAG A COLD FRONT ACROSS THE AREA DURING 
THE NIGHT. CATEGORICAL POPS FOR WEDS/WEDS EVENING BEFORE THE COLD 
FRONT MOVES THROUGH...THEN JUST LOW CHANCES OF SHOWERS AFTER 
MIDNIGHT...MAINLY EAST OF THE CITY. RAINFALL EXPECTED TO BE MOSTLY 
ON THE MODERATE SIDE WITH MINOR URBAN FLOODING POSSIBLE. FOR 
THURSDAY A STRONG FETCH OFF OF LAKE ERIE COULD BRING A RAIN OR SNOW 
SHOWER TO THE FAR NW PORTION OF THE CWA THURSDAY MORNING.

BREEZY CONDITIONS FOR WEDS THRU THURS. A STRONG LOW LEVEL JET PUSHES 
THROUGH THE EASTERN ZONES WEDS AFTN/EVE...BUT STRONG GUSTS WILL 
PROBABLY HAVE A TOUGH TIME MIXING DOWN THROUGH AN INVERSION. 
STRONGER GUSTS MAY BE REALIZED DURING THURSDAY BEHIND THE COLD FRONT 
COURTESY OF BETTER MIXING. MARGINAL ADVISORY CRITERIA GUSTS COULD BE 
POSSIBLE WEDS AFTN THRU THURS. TEMPS DURING THIS PERIOD WILL BE 
ABOVE AVERAGE. HIGHS ON WEDS IN THE 50S...AND WITH A MODERATE WSW 
FLOW AND PARTIAL SUNSHINE ON THURSDAY...HIGH TEMPS WELL INTO THE 40S 
EXPECTED.

HIGH PRESSURE BUILDS IN FOR FRIDAY WITH LIGHTER WINDS AND CLOSER TO 
NORMAL TEMPERATURES.

&&

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE GRADUALLY BUILDS EAST INTO NEW ENGLAND THROUGH TONIGHT.

CIGS EXPECTED TO CONTINUE TO VARY BETWEEN SCT-BKN 3000-3500 FT 
THROUGH THIS MORNING AS MOISTURE REMAINS TRAPPED UNDER AN INVERSION. 
EASTERN TERMINALS MAY SEE A PERIOD OF CLEARING EARLY THIS MORNING 
BASED ON UPSTREAM DRYING SEEN ON SATELLITE...WHILE STRATUS MAY 
BECOME MORE WIDESPREAD ACROSS CITY AND WESTERN TERMINALS. LOW 
CONFIDENCE ON COVERAGE OF STRATUS THROUGH THIS MORNING.  

INCREASING CHANCES FOR WIDESPREAD BKN MVFR CIGS THIS AFTERNOON INTO 
EVENING.

320-350 MAGNETIC WINDS CONTINUE TO VEER TO THE NORTH AND DECREASE 
EARLY THIS MORNING. LIGHT N-NE WINDS LESS THAN 8 KT DURING TH DAY 
INTO EVENING. 

.OUTLOOK FOR 06Z SUN THROUGH WED...
.LATE TONIGHT...MVFR CIGS LIKELY...WITH LIGHT SNOW SHOWERS POSSIBLE 
FOR EASTERN TERMINALS. LIGHT NORTHEAST WINDS.
.SUNDAY...MVFR CIGS...WITH LIGHT SNOW/RAIN SHOWERS POSSIBLE FOR
CITY/COASTAL TERMINALS. LIGHT NORTHEAST WINDS.
.MON...MVFR OR LOWER POSSIBLE IN E-SE FLOW. CHC OF RAIN.
.MON NIGHT-TUE...IFR LIKELY AT TIMES IN RAIN...CIGS AND VSBYS. E-SE 
WINDS 10-20 KT. 
.TUE NIGHT AND WED...HIGH IMPACT EVENT POSSIBLE...IFR LIKELY WITH 
HEAVY RAIN AND GUSTY SE WINDS 25KT+ SHIFTING TO SW LATE WED.

&&

.MARINE...
WITH HIGH PRES BUILDING OVER THE WATERS...CAN EXPECT NORTH WINDS 10 
KT OR LESS THROUGH THE WEEKEND ALONG WITH SEAS GENERALLY 1-2 FT ON 
THE OCEAN OR 1 FT OR LESS ON ALL OTHER WATERS.

EASTERLY FLOW DEVELOPS ON MONDAY AS LOW PRES PASSES SOUTH OF THE 
WATERS EARLY IN THE NEW WEEK. SMALL CRAFT ADVISORY CONDS DEVELOP ON 
TUESDAY AS GRADIENT TIGHTENS. ANOTHER LOW DEVELOPS OVER THE 
MID-ATLANTIC AREA AND TRACKS NORTH THROUGH THE WATERS WEDNESDAY AND 
WEDNESDAY NIGHT. THAT LOW RAPIDLY DEEPENS OVER CANADA ON THURSDAY... 
ALLOWING THE GRADIENT TO TIGHTEN OVER THE WATERS. SMALL CRAFT 
ADVISORY CONDS EXPECTED THROUGH WEDNESDAY...AND THEN GALES ARE 
LIKELY THURSDAY AND THURSDAY NIGHT.

&&

.HYDROLOGY...
NO HYDRO IMPACTS EXPECTED INTO EARLY NEXT WEEK.

AROUND A QUARTER INCH OF RAIN IS POSSIBLE IS POSSIBLE MONDAY 
AFTERNOON THROUGH TUESDAY AS LOW PRES PASSES SOUTH OF LONG ISLAND. 
NO HYDROLOGICAL IMPACTS EXPECTED.

RAIN ON WED/WED NIGHT MAY AVERAGE 1-2 INCHES ACROSS THE REGION. 
MINOR URBAN FLOODING IS POSSIBLE.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...JC
NEAR TERM...JC
SHORT TERM...JC
LONG TERM...JC
AVIATION...MPS
MARINE...MPS
HYDROLOGY...JC






National Weather Service
Disclaimer Privacy Policy