Area Forecast Discussion
Issued by NWS Upton, NY

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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 261612
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1212 PM EDT THU MAR 26 2015

.SYNOPSIS...
A COLD FRONT PASSES TONIGHT. A WEAK TROUGH MOVES THROUGH FRIDAY
NIGHT INTO SATURDAY...BEHIND THE DEPARTING LOW. HIGH PRESSURE
BUILDS IN SUNDAY. ANOTHER FRONTAL SYSTEM MOVES THROUGH
MONDAY...FOLLOWED BY HIGH PRESSURE FOR TUESDAY. A FRONTAL SYSTEM
WILL APPROACH LATE WEDNESDAY INTO THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FCST UPDATED MAINLY FOR MARINE HEADLINES. WITH LIFT SUPPLIED BY A
LOW LEVEL JET AND PLENTY OF MOISTURE IN PLACE...RAIN PUSHES IN
FROM THE SOUTH INTO EARLY AFTERNOON. THIS LIFT...COMBINED WITH
SOME ELEVATED CAPE AND MARGINALLY UNSTABLE MID LEVEL LAPSE
RATES...COULD RESULT IN AN ISOLATED RUMBLE OF THUNDER AS WELL.
BETTER OVERALL CHANCES OF THUNDER WOULD BE OVER THE EASTERN HALF
OF THE AREA...BUT WILL LEAVE IN MENTION OF THUNDER ACROSS THE
ENTIRE AREA. EXPECTING PATCHY/AREAS OF FOG AS WELL...AND SOME OF
THIS FOG COULD BE LOCALLY DENSE. NOT ENOUGH CONFIDENCE IN
WIDESPREAD DENSE FOG TO GO WITH A DENSE FOG ADVISORY AT THIS
POINT. BUT THIS WILL NEED TO BE WATCHED...ESPECIALLY OVER THE
EASTERN HALF OF THE CWA WHERE RELATIVELY HIGHER DEWPOINTS ADVECT
FROM OFF THE COLD AREA WATERS.

OTHER CONCERN IS FOR LOCALIZED FLASH FLOODING...PARTICULARLY OVER
EASTERN CT WHERE RAINFALL THIS AFTERNOON COULD BE BRIEFLY HEAVY DUE
TO CONVECTION...AND COINCIDING WITH WHERE SNOW MELT CAN CONTRIBUTE TO
RUNOFF. OVERALL THREAT IS LOW...SO NO WATCH IS PLANNED FOR THIS.

USED A NAM/MAV MOS BLEND FOR HIGH TEMPERATURES...WHICH BRINGS THEM
ABOVE NORMAL.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
A COLD FRONT SLOWLY PASSES THROUGH WITH MORE RAINFALL. STILL ENOUGH
ELEVATED CAPE TO MENTION ISOLATED THUNDER...BUT MAINLY FOR THE
EVENING. MODELS HAVE TRENDED SLOWER WITH THE END TIME OF
RAINFALL...SO EVEN BY DAYBREAK FRIDAY...WILL CARRY LIKELY POPS FOR A
GOOD PORTION OF THE CWA. POPS THEN GRADUALLY LOWER INTO FRIDAY
AFTERNOON....WITH AT LEAST THE WESTERN HALF OF THE CWA AT A HIGH
CHANCE OF REMAINING DRY DURING THE AFTERNOON. COLD ADVECTION BEHIND
THE COLD FRONT WILL BE DELAYED SOMEWHAT...SO HIGHS WILL MANAGE TO
AVERAGE NEAR 50.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
BROAD UPPER LEVEL TROUGH REMAINS OVER THE EAST COAST FRIDAY NIGHT
INTO SATURDAY WITH THE TROUGH AXIS MOVING EAST OF THE REGION LATE
SATURDAY NIGHT INTO SUNDAY. COLD AIR ADVECTION ON SATURDAY WILL MEAN
LOWER THICKNESSES AND COLDER TEMPERATURES...GENERALLY 30S REGION-
WIDE. SHORTWAVE ENERGY WILL ROTATE THROUGH THE UPPER TROUGH WHILE AT
THE SURFACE A WEAK TROUGH REMAINS BEHIND DEPARTING LOW PRESSURE. THE
COMBINATION WILL PROVIDE ENOUGH LIFT WITH LINGERING LOW LEVEL
MOISTURE. WITH COLDER AIR IN PLACE...MOST OF THE AREA WILL SEE SNOW
SHOWERS SATURDAY MORNING...CHANGING OVER TO RAIN SHOWERS BY LATE
MORNING INTO THE AFTERNOON. PRECIPITATION LINGERS INTO SATURDAY
NIGHT.

SURFACE HIGH PRESSURE BUILDS IN FOR SUNDAY...THEN MOVES OFF THE
COAST SUNDAY NIGHT. RIDGING ALOFT OVER THE NORTHEAST ALONG WITH
DEEPENING LOW PRESSURE MOVING INTO THE GREAT LAKES WILL ALLOW FOR
WARM ADVECTION AHEAD OF THE LOW. TEMPERATURES WILL WARM INTO THE
40S. LOOKS LIKE ANY PRECIPITATION FROM THIS SYSTEM WILL HOLD OFF
UNTIL MONDAY MORNING.

COLD FRONT MOVES THROUGH MONDAY. THERE IS LIMITED MOISTURE TO WORK
WITH...SO WILL CONTINUE WITH JUST SLIGHT CHANCE POPS.

WITH LOWER AMPLITUDE UPPER FLOW SYSTEMS QUICKLY MOVE EAST. AS A
RESULT...HIGH PRESSURE BUILDS MONDAY NIGHT INTO TUESDAY. SOME
UNCERTAINTY FOR THE AREA OF LOW PRESSURE THAT APPROACHES FOR
WEDNESDAY. FOR NOW...WILL KEEP SLIGHT CHANCE POPS FOR WEDNESDAY.
ANOTHER FRONTAL SYSTEM APPROACHES LATE WEDNESDAY NIGHT INTO
THURSDAY...WITH A WARM FRONT MOVING THROUGH THE AREA DURING THIS
TIME PERIOD.

&&

.AVIATION /16Z THURSDAY THROUGH MONDAY/...
A WARM FRONT WILL LIFT THROUGH LATE THIS MORNING AND EARLY THIS
AFTERNOON. A COLD FRONT WILL THE MOVE ACROSS TONIGHT.

WARM FRONT AT 14Z EXTENDED FROM CENTRAL NJ UP TO NEAR KISP TO
SOUTH OF MONTAUK...AND WILL CONTINUE TO SLOWLY LIFT NORTHWARD.
OUT AHEAD OF THE FRONT...CONDS ARE MAINLY IFR BUT HAVE IMPROVED
TO MVFR IN SPOTS MAINLY AROUND NYC METRO. AS A WEAKENING CLUSTER
OF SHOWERS AND ISOLD TSTMS MOVES NE INTO THE AREA EARLY THIS
AFTERNOON...REACHING NYC METRO/LONG ISLAND BY 17Z AND CT BY 18Z...
CONDS SHOULD LOWER TO IFR. ATTM THINK THUNDER WILL AVOID NYC
METRO...BUT MAY BRIEFLY IMPACT KISP IF THE CLUSTER HOLDS TOGETHER.
AFTER THIS CLUSTER PASSES...HIGHER DEWPOINT AIR MOVING OVER COLD
OCEAN WATERS SHOULD LEAD TO REDEVELOPMENT OF IFR CONDS LATER THIS
AFTERNOON AND THIS EVENING AHEAD OF THE APPROACHING COLD FRONT.
MEDIUM POTENTIAL EXISTS FOR LIFR/VLIFR CONDS AT
KJFK/KHPN/KBDR/KGON/KISP...WITH A LOWER POTENTIAL AT KLGA/KEWR/KTEB.
GRADUAL IMPROVEMENT TO MVFR EXPECTED AFTER COLD FROPA TONIGHT.

SOUTH WINDS AFTER WARM FROPA WILL INCREASE TO 10-20KT MID TO LATE
AFTERNOON...WITH A FEW GUSTS 25-30 KT POSSIBLE. WINDS SHIFT WSW
AND THEN NW AFTER COLD FROPA BETWEEN 00Z AND 06...WITH GUSTS
15-20 KT.

LLWS EXPECTED THIS AFTERNOON/EVENING FOR COASTAL TERMINALS...WITH
SW WINDS 55-65 KT AT 2 KFT AGL AT THE CT/LONG ISLAND TERMINALS...
AND 45-55 KT AT THE NYC METRO TERMINALS.

     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: MEDIUM CONFIDENCE IN LIFR OR LOWER VSBY
LATE THIS AFTERNOON INTO EVE.

KLGA FCSTER COMMENTS: UNSCHEDULED AMD POSSIBLE FOR CHANGES IN
FLIGHT CATEGORY.

KEWR FCSTER COMMENTS: UNSCHEDULED AMD POSSIBLE FOR CHANGES IN
FLIGHT CATEGORY.

KTEB FCSTER COMMENTS: UNSCHEDULED AMD POSSIBLE FOR CHANGES IN
FLIGHT CATEGORY.

KHPN FCSTER COMMENTS: MEDIUM TO HIGH CONFIDENCE IN LIFR/VLIFR
CONDS RE-DEVELOPING LATE THIS AFTERNOON AND THIS EVENING.

KISP FCSTER COMMENTS: MEDIUM TO HIGH CONFIDENCE IN LIFR/VLIFR
CONDS PREVAILING INTO THIS EVENING.

.OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...
.FRI...BECOMING VFR...WITH RAIN TAPERING OFF.
.FRI NIGHT-SAT...CHANCE OF MVFR CONDS WITH ANY RAIN OR SNOW
SHOWERS. N-NE WINDS G15-25KT.
.SAT NIGHT-MON...VFR. SW-W WINDS G15-25KT.

&&

.MARINE...
A COLD FRONT MOVES ACROSS THE WATERS TONIGHT BEFORE BECOMING
NEARLY STATIONARY ACROSS THE OCEAN WATERS ON FRIDAY.

THE PRESSURE GRADIENT WILL TIGHTEN TODAY...AND SMALL CRAFT ADVISORY
CONDITIONS WILL DEVELOP ON THE OCEAN AND SOUTH SHORE BAYS THIS
AFTERNOON. WINDS FALL BELOW SCA CONDITIONS ON THE SS BAYS
TONIGHT...BUT SEAS WILL REMAIN ELEVATED ON THE OCEAN WATERS THROUGH
AT LEAST FRIDAY.

WAVES REMAIN AT OR ABOVE 5 FT FRIDAY NIGHT INTO SATURDAY WITH A
STRONG NORTHWEST FLOW BETWEEN DEPARTING LOW PRESSURE TO THE EAST AND
HIGH PRESSURE BUILDING TO THE WEST. ALSO...GUSTS ON THE OCEAN WATERS
MAY APPROACH SMALL CRAFT FOR A WHILE SATURDAY.

THE FLOW SUNDAY NIGHT INTO MONDAY BECOMES WEST THEN SOUTHWEST AS
HIGH PRESSURE MOVES EAST AND ANOTHER LOW APPROACHES. WIND AND WAVES
WILL BE ABOVE SCA CRITERIA FOR MONDAY THROUGH TUESDAY. GALE FORCE
WINDS ARE POSSIBLE MONDAY NIGHT INTO TUESDAY. WAVES COME DOWN BELOW
5 FT ON TUESDAY. WINDS STAY ABOVE SCA THROUGH TUESDAY NIGHT.

&&

.HYDROLOGY...
AN ADDITIONAL 1/2 TO 3/4 INCH OF RAIN IS EXPECTED THROUGH FRIDAY.
THEREAFTER...SIGNIFICANT PRECIPITATION IS NOT EXPECTED FRIDAY NIGHT
THROUGH THE BEGINNING OF THE NEW WEEK.

THE RAINFALL AND SNOW MELT WILL RESULT IN MINOR TO MODERATE RISES
ON RIVERS/STREAMS ACROSS MAINLY SOUTHERN CONNECTICUT AND LOWER
HUDSON RIVER VALLEY DURING THE LATE WEEK PERIOD...POSSIBLY INTO
THIS WEEKEND.

CURRENTLY RIVERS AND STREAMS ARE EXPECTED TO REMAIN BELOW
BANK FULL...BUT THE MILD TEMPS AND INCREASED RIVER/STREAM FLOW
WILL INCREASE ICE BREAKUP AND MOVEMENT DURING THE NEXT FEW DAYS.
ISOLATED ICE JAMS ARE POSSIBLE...WHICH IF THEY OCCUR...COULD
RESULT IN LOCALIZED FLOODING. SINCE ICE JAM FLOODING IS
UNPREDICTABLE AND SUDDEN...INTERESTS ALONG ICE COVERED RIVERS
SHOULD MONITOR NWS FORECASTS FOR THE LATEST INFORMATION.

FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEB SITE.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ350-353-355.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ345.

&&

$$
SYNOPSIS...JC/JP
NEAR TERM...JMC/JC
SHORT TERM...JC
LONG TERM...JP
AVIATION...GOODMAN/NV
MARINE...JMC/JC/JP
HYDROLOGY...JC/JP


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