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Area Forecast Discussion
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000
FXUS61 KOKX 192001
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
401 PM EDT SUN OCT 19 2014

.SYNOPSIS...
HIGH PRESSURE BUILDS TO THE SOUTH TONIGHT AND THEN OFF THE MID
ATLANTIC COAST ON MONDAY, LOW PRESSURE WILL THEN APPROACH FROM
THE GREAT LAKES MONDAY NIGHT. SECONDARY LOW PRESSURE DEVELOPS
NEAR THE MID-ATLANTIC COAST BY LATE TUESDAY...THEN SLOWLY MEANDERS
TO THE GULF OF MAINE BY FRIDAY MORNING...THEN TO THE CANADIAN
MARITIME PROVINCES BY SATURDAY MORNING. A COLD FRONT APPROACHES
FROM THE NORTHWEST SATURDAY...THEN CROSSES THE AREA SATURDAY
NIGHT. HIGH PRESSURE BUILDS IN FROM SOUTH CENTRAL CANADA SUNDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
MEAN TROF RESIDES ACROSS THE EASTERN U.S. AS IT ONCE AGAIN WILL
RELOAD WITH SHORT WAVE ENERGY ACROSS THE UPPER MIDWEST...CARVING
OUT ANOTHER AMPLIFIED TROF ACROSS THE GREAT LAKES AND OHIO VALLEY
STATES BY MON NIGHT. PRIOR TO THAT TIME...RIDGING BOTH ALOFT AND AT
THE SFC MOVES INTO THE AREA TONIGHT. GUSTY NW WINDS EARLY THIS
EVENING WILL FALL OFF QUICKLY.

THE COMBINATION OF A LIGHT W/NW FLOW OVERNIGHT...MAINLY CLEAR
SKIES...AND A DRY AIR MASS WILL ALLOW INTERIOR LOCATIONS TO DROP
TO AROUND FREEZING AND MOST OTHER LOCATIONS OUTSIDE OF METRO NY
INTO THE UPPER 30S. FREEZE WARNINGS AND FROST ADVISORIES REMAIN UP
FOR MOST LOCATIONS WITH THE EXCEPTION OF NYC METRO AND WESTERN LI.
THE AVERAGE FIRST AUTUMN FREEZE IS OCTOBER 21 FOR THE INTERIOR...SO
THIS RIGHT ON TIME FROM A CLIMATOLOGICAL PERSPECTIVE. MOST LOCATIONS
WILL BE ABOUT 5 TO 10 DEGREES BELOW NORMAL. THERE ARE THOUGH A
COUPLE OF LIMITING FACTORS THAT WILL HAVE TO BE WATCHED TONIGHT
WITH THE POTENTIAL FOR HIGH CLOUDS TO MOVE IN FROM THE MIDWEST
AND THE AIR MASS PERHAPS BEING JUST DRY ENOUGH TO LIMIT FROST
FORMATION.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
HIGH PRESSURE WILL MOVE OFF THE MID ATLANTIC COAST ON MON WITH A
RETURN SW FLOW...WHILE LOW PRESSURE DROPS SE ACROSS THE GREAT
LAKES. THERE IS SOME UNCERTAINTY WITH THE OPAQUENESS OF THE MID AND
HIGH LEVEL CLOUDS AND THE AMOUNT OF SUN FILTERING THROUGH.
CONDITIONS WILL LIKELY START OFF PARTLY TO MOSTLY SUNNY...BUT
BECOME MOSTLY CLOUDY LATE AS MID LEVEL CLOUDS FILTER IN FROM THE
WEST. HIGHS ON MON WILL BE A TOUCH WARMER WITH A SW FLOW...BUT A
SUBSIDENCE INVERSION WILL INHIBIT DEEP MIXING...WITH HIGH ONLY IN
THE MID AND UPPER 50S.

FOR MON NIGHT...WEAK LIFT AND DEEPENING MOISTURE MAY RESULT IN
SOME SHOWER ACTIVITY AFTER MIDNIGHT. RAINFALL AMOUNTS WILL BE
LIGHT. HEIGHTS BEGIN TO FALL LATE AT NIGHT IN RESPONSE TO THE
APPROACHING LONGWAVE TROF TO THE WEST. 

LOWS WILL BE CONSIDERABLY WARMER DUE TO THE CLOUD COVER AND SW
FLOW...WITH MOST LOCATIONS 45 TO 50.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
MODELS START OUT IN SOLID AGREEMENT ON OVERALL PATTERN...AND MOST 
DETAILS ON TUESDAY...BUT THEN BEGIN TO DIVERGE LATTER IN THE 
WEEK...ESPECIALLY ON THE HANDLING OF SYSTEMS TO THE WEST OF THE 
CUTOFF LOW THAT EXITS TO OUR NORTHEAST LATE THIS WEEK. USED A BLEND 
OF ALL AVAILABLE GUIDANCE THROUGH FRIDAY NIGHT...THEN LEANED TOWARDS 
THE ECMWF FOR SATURDAY THROUGH SUNDAY. I USED THIS BLEND LATE IN THE 
PERIOD DUE TO THE ECMWF BETTER RUN TO RUN CONSISTENCY...THE GEFS 
ENSEMBLES SUPPORTING A LESS PROGRESSIVE PATTERN...ESPECIALLY WITH 
REGARDS TO THE LARGE AMPLITUDE RIDGE TO OUR WEST...AND BETTER 
HISTORICAL VERIFICATION OF THE ECMWF IN THIS TIME FRAME.

THE WEATHER WILL BE UNSETTLED FROM TUESDAY INTO AT LEAST FRIDAY AS A 
CUTOFF LOW INITIALLY TRACKS TO OUR S...THEN MEANDERS NEAR US DURING 
THE MIDDLE OF THE WEEK...THEN SLOWLY LIFTS TO THE NORTHEAST TO THE 
CANADIAN MARITIMES BY THE WEEKEND. HOWEVER...WITH THE CUTOFF LOW SO 
CLOSE TO THE REGION...WOULD NOT EXPECT CONTINUOUS PRECIPITATION 
DURING THIS TIME FRAME. ISENTROPIC LIFT OF ANY SIGNIFICANCE APPEARS 
TO HOLD OFF UNTIL TUESDAY NIGHT...SO ONLY FORECASTING A CHANCE OF 
SHOWERS ON TUESDAY - EXCEPT LIKELY W 1/3 OF CWA CLOSER TO CLOSED 
LOW. THEN HAVE RAIN LIKELY TUESDAY NIGHT-WEDNESDAY IN RESPONSE TO 
DECENT ISENTROPIC LIFT - ULTIMATELY WILL LIKELY END UP BEING PERIODS 
OF RAIN IN THIS TIME FRAME...LINGERING LIKELY POPS INTO WEDNESDAY 
NIGHT AS BEST ISENTROPIC LIFT TRANSITIONS EAST WITH FORECAST TRACK 
OF SURFACE LOW. HAVE LIKELY POPS ON THURSDAY ACROSS NORTHERN ZONE IN 
RESPONSE TO LIKELY LOCATION OF DEFORMATION AXIS AS CLOSED LOW BEGINS 
TO LIFT TO THE NE. THEN LINGER CHANCE POPS INTO FRIDAY AS THE LOW 
LIFTS FARTHER NE.

FOR NOW GOING DRY FRIDAY NIGHT-SUNDAY...AS APPEARS WILL BE LIMITED 
LOW LEVEL MOISTURE AVAILABLE FOR PASSING COLD FRONT/NORTHERN STREAM 
TROUGH TO ACT ON SATURDAY NIGHT...WITH WEAK RIDGING AHEAD OF THE 
TROUGH. SHOULD THEN HAVE A DRY NW FLOW ON THE BACKSIDE OF THE 
TROUGH.  

FOR HIGHS ON TUESDAY USED A BLEND OF MAV/MET/ECS GUIDANCE WITH NAM 
2-METER TEMPERATURES AND A MIX DOWN FROM 925-875 HPA PER BUFKIT 
SOUNDINGS. EXPECT HIGHS TO BE NEAR TO SLIGHTLY ABOVE NORMAL. A BLEND 
OF MAV AND MET GUIDANCE WITH NAM 2-METER TEMPERATURES WAS USED FOR 
LOWS TUESDAY NIGHT WITH READINGS FORECAST TO BE 5 TO 10 DEGREES 
ABOVE NORMAL. ON WEDNESDAY A BLEND OF MEX/MEN/EKD/ECE/ECM/WPC 
GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX DOWN FROM 950 HPA 
PER BUFKIT SOUNDINGS WAS USED FOR HIGHS. EXPECT VALUES TO BE AROUND 
5 DEGREES BELOW NORMAL.

FROM WEDNESDAY NIGHT THROUGH SUNDAY A BLEND OF 
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE WAS USED FOR TEMPERATURES. LOWS 
WILL RUN SLIGHTLY ABOVE NORMAL IN THIS TIME FRAME...AND AFTER 
SLIGHTLY BELOW NORMAL HIGHS ON THURSDAY...HIGHS WILL RUN NEAR TO 
SLIGHTLY ABOVE NORMAL AS WELL FRIDAY THROUGH SUNDAY.

IT SHOULD BE NOTED THAT HIGHS ON SUNDAY COULD END UP BEING SOME 5-10 
DEGREES COLDER THAN FORECAST IF THE ECMWF VERIFIES - IN RESPONSE TO 
SHALLOW LOW LEVEL COLD ADVECTION BEHIND THE COLD FRONT.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
FORECAST REMAINS ON TRACK...SO WILL ONLY MAKE MINOR ADJUSTMENTS TO 
THE TAFS BASED ON LATEST SFC OBS.

NW WINDS...JUST AT OR TO THE RIGHT OF 310 MAGNETIC...WILL AVERAGE 
15-20 KT WITH 25-30 KT GUSTS THROUGH AROUND 22Z. WINDS DIMINISH TO 
10-15 KT WITH 15-20 KT GUSTS BY THEREAFTER...AND THEN WINDS WILL 
DIMINISH TO 10 KT OR LESS BETWEEN 00-02Z MONDAY.

WINDS GRADUALLY BACK TO THE W-SW THROUGH THE OVERNIGHT...AND THEN
WINDS BACK TO THE S BY MONDAY AFTERNOON.

VFR. SCT CLOUDS AT 040-050 THROUGH EARLY THIS EVENING. SKC CONDS BY 
02Z. BKN CIGS AT 15 KFT WILL DEVELOP BY MONDAY AFTERNOON.

.OUTLOOK FOR 21Z MONDAY THROUGH FRIDAY...
.MONDAY AFTERNOON...VFR. S-SW WINDS 10 KT OR LESS.
.MONDAY NIGHT THROUGH THURSDAY...MVFR OR LOWER CONDS IN RAIN. BEST
CHANCES TUESDAY THROUGH WEDNESDAY. 
.FRIDAY...IMPROVING CONDS. NW WINDS 15-20 KT WITH 20-25 KT GUSTS.

&&

.MARINE...
SCA WILL COME DOWN FROM WEST TO EAST ACROSS THE WATERS
TONIGHT...WITH THE EASTERN OCEAN WATERS TAKING THE LONGEST. HIGH
PRESSURE BUILDS IN FROM THE WEST WITH A DIMINISHING NW FLOW...AND
SWELLS FROM DISTANT HURRICANE GONZALO CONTINUE TO DIMINISH. HIGH
PRESSURE WILL THEN PASS OFF THE MID ATLANTIC COAST MON WITH A
RETURN SW FLOW. CONDITIONS ARE FORECAST TO REMAIN BELOW SCA
CRITERIA THROUGH MON NIGHT.

SUB-SMALL CRAFT CONDITIONS ARE MOST LIKELY ON ALL WATERS TUESDAY 
THROUGH FRIDAY. WIND GUSTS SHOULD BE AROUND 20 KT FROM WEDNESDAY 
INTO THURSDAY NIGHT...AND COULD POSSIBLY REACH 25 KT MAINLY ON THE 
COASTAL OCEAN WATERS IN THIS TIME FRAME. ALSO...SEAS ON THE COASTAL 
OCEAN WATERS EAST OF MORICHES INLET COULD REACH 5 FT ON 
WEDNESDAY...AND POSSIBLY ON THE REMAINDER OF THE COASTAL OCEAN 
WATERS FROM WEDNESDAY NIGHT INTO THURSDAY NIGHT.

FOR NOW THERE IS TOO MUCH UNCERTAINTY TO FORECAST SMALL CRAFT 
CONDITIONS DURING THE MIDDLE OF THE WEEK..EXCEPT FOR THE SCA LEVEL 
SEAS EAST OF MORICHES INLET ON WEDNESDAY. 

&&

.HYDROLOGY...
THERE IS THE POTENTIAL FOR AROUND AN INCH OF RAIN FROM TUESDAY INTO 
THURSDAY. BECAUSE THIS WILL BE SPREAD OVER AROUND 48 HOURS...THERE 
DOES NOT APPEAR TO BE AN SIGNIFICANT HYDROLOGIC IMPACT EXPECTED AT 
THIS TIME.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR 
     CTZ009>012.
     FREEZE WARNING FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR 
     CTZ005>008.
NY...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR 
     NYZ069-070-079>081.
     FREEZE WARNING FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR 
     NYZ067-068.
NJ...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR 
     NJZ004-103-105-107.
     FREEZE WARNING FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR 
     NJZ002.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ335-
     338-345.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ330-340-
     355.
     SMALL CRAFT ADVISORY UNTIL 5 AM EDT MONDAY FOR ANZ350-353.

&&

$$

SYNOPSIS...MALOIT/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...MALOIT
AVIATION...MPS
MARINE...MALOIT/DW
HYDROLOGY...MALOIT/DW






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