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000
FXUS61 KOKX 120712
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
312 AM EDT WED MAR 12 2014

.SYNOPSIS...
AN INTENSIFYING LOW PRESSURE SYSTEM WILL PASS ACROSS THE REGION
WEDNESDAY EVENING. AN ARCTIC BLAST OF COLD AIR MOVES OVER THE
REGION FOR THURSDAY WITH HIGH PRESSURE BUILDING IN. A COLD FRONT
WILL PASS THROUGH LATE ON SATURDAY...WITH MORE COLD HIGH PRESSURE
FOR SUNDAY. LOW PRESSURE TRACKS SOUTH OF REGION EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
WINDS REMAIN GENERALLY LIGHT ACROSS THE AREA AS OF MIDNIGHT. THIS
SHOULD CONTINUE FOR A FEW MORE HOURS BEFORE THEY BEGIN TO PICK UP
OUT OF THE E/SE TOWARDS DAYBREAK WITH THE TIGHTENING PRESSURE
GRADIENT.

T/TD FORECAST GENERALLY ON TRACK. TWEAKED TEMPS UP A COUPLE DEGREES
IN MOST LOCATIONS BASED ON TRENDS. CLOUDS/DEVELOPING WEAK WAA
SHOULD KEEP TEMPS FROM DROPPING MUCH FURTHER OVERNIGHT.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM THURSDAY/...
WHILE THERE ARE SOME MINOR VARIATION IN THE NWP IN TERMS OF THE SYNOPTIC
FEATURE...SPREAD IS RATHER LOW AND FEEL CONFIDENT WITH A LOW
TRACKING DIRECTLY OVER NYC/LONG ISLAND WEDNESDAY EVENING.

PCPN START TIME IS DELAYED UNTIL AFTERNOON WITH JUST A LOW CHANCE
IN THE AM FOR NORTHERN AREAS. THIS BASED ON A CONSENSUS OF THE NWP
WITH THE OPERATIONAL GFS BEING THE EXCEPTION. THE GFS HAD QPF OUT
OF CLEAR SKIES IN WV TODAY...SO FEEL IT IS OVER DOING THE OVER-
RUNNING IN THE AM.

REGARDLESS...POPS STILL INCREASE TO 100 IN THE AFTERNOON. STRONG
INVERTED BOUNDARY LAYER PROFILE PREVENTS 60-70 KT LLJ AT 2 KFT AGL
FROM TRANSLATING TO SURFACE.

FROPA LOOKS TO BE IN THE 03-06Z TIME FRAME FROM WEST TO EAST WITH
PLUMMETING TEMPS IN THE WAKE OF THE FRONT. MID TEENS NORTH TO MID 20S
ON EASTERN LI BY MORNING.

THE QUESTION IS HOW MUCH PCPN WILL BE ON THE BACKSIDE. BASED ON
LATEST NWP AND THE TRANSIENT NATURE OF THE LOW...ONLY EXPECTED
LIGHT PCPN ON THE THE BACKSIDE. SNOW TOTALS OF LESS THAN AN INCH
EXCEPT FAR NORTH. COASTAL AREAS LOOK CLOSER TO A COATING.

REGARDLESS...THE RAPID DROP OF TEMPS RESULTS IN MODERATE
CONFIDENCE FOR A FLASH FREEZE EVENT IN THE PREDAWN HOURS OF
THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
TWO SYSTEMS OF INTEREST IN THE LONG TERM...THE FIRST THE DEPARTING
COASTAL LOW THURSDAY-FRIDAY AND THE SECOND A POSSIBLE COASTAL LOW
FOR EARLY NEXT WEEK.

FOR THE FIRST SYSTEMS...APPEARS TO BE GOOD AGREEMENT THAT
LIKELY SEE WIND ADVISORY CRITERIA WINDS ACROSS AT LEAST NYC/LONG
ISLAND/COASTAL CT AND SOUTHERN/EASTERN PORTIONS OF NE NJ/LOWER
HUDSON VALLEY...WITH A POSSIBILITY OF ADVISORY LEVEL WINDS ACROSS
INTERIOR/WESTERN LOWER HUDSON VALLEY AND NE NJ ZONES. AT THIS
TIME...WITH ONLY THE ECMWF HAVING 850 WINDS OF 50 KT...PROBABILITY
OF REACHING HIGH WIND WARNING CRITERIA IS LOW. THE STRONGEST WINDS
SHOULD BE DURING THE MORNING HOURS...THEN DIMINISHING THROUGH THE
THURSDAY AFTERNOON INTO FRIDAY. ANY WINDS TO ADVISORY CRITERIA
SHOULD COME TO AN END DURING THURSDAY AFTERNOON FROM W TO E.

WITH THE STRONG NW WINDS ADVECTING IN A VERY COLD AIR MASS FOR THIS
TIME OF YEAR...DO NOT EXPECT TEMPERATURES TO RISE MUCH...IF AT ALL
DURING THE DAY ON THURSDAY. USED A BLEND OF MAV/MET GUIDANCE WITH
NAM 2-METER TEMPERATURES AND A MIX DOWN FROM 875 HPA FOR HIGHS
THURSDAY...WITH READINGS STRUGGLING TO REACH THE UPPER TEENS TO
AROUND 20 ACROSS THE INTERIOR AND THE LOWER TO MID 20S ELSEWHERE.

THESE COLD TEMPERATURES COUPLED WITH THE AFOREMENTIONED STRONG
WINDS WILL ALLOW FOR WIND CHILLS AT BEST IN THE SINGLE DIGITS
THURSDAY...AND POSSIBLY IN THE SINGLE DIGITS BELOW ZERO ACROSS
HIGHER ELEVATIONS.

ALSO IN THE WAKE OF THE DEPARTING LOW...HAVE THE CHANCE FOR MAINLY
SCT -SHSN THURSDAY MORNING...TAPERING OFF BY EARLY AFTERNOON FROM
SW TO NE.

THURSDAY NIGHT WILL HAVE CLEARING WITH SLOWLY DIMINISHING
WINDS...AND WILL CONTINUE TO BE VERY COLD. FOR LOWS USED THE
LOWEST OF NAM 2-METER TEMPERATURES AND MAV AND MET
GUIDANCE...WITH VALUES APPROACHING RECORD LEVELS BY EARLY FRIDAY
MORNING. COUPLED WITH BRISK NW WINDS...WILL SEE WIND CHILLS AS 0
TO -5 ACROSS THE INTERIOR AND 0 TO 5 ABOVE ACROSS COASTAL AREAS
OVERNIGHT THURSDAY NIGHT.

WEAK RIDGING TRANSITS ACROSS THE AREA FRIDAY...KEEPING THINGS
DRY. FOR HIGHS FRIDAY USED A BLEND OF MIXING DOWN FROM 925 HPA PER
BUFKIT SOUNDINGS...NAM 2-METER TEMPERATURES AND A BLEND OF
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE - WITH VALUES AROUND 10 DEGREES
BELOW NORMAL.

SOME DIFFERENCES IN TIMING AND STRENGTH OF NORTHERN STREAM
SHORTWAVES FORECAST TO TRACK TO THE N/W OF THE AREA FRIDAY NIGHT
AND SATURDAY. GIVEN UNCERTAINTY AND WITH CORE OF ENERGY PASSING
WELL TO THE N/W...HAVE LIMITED ANY POPS TO SLIGHT CHANCE IN THIS
TIME FRAME. THE LAST OF THESE SHORTWAVES BRINGS ANOTHER POLAR
COLD FRONT THROUGH LATE SATURDAY...WITH CANADIAN HIGH PRESSURE
BUILDING IN BEHIND IT. THIS LOW LEVEL COLD AIR AND THE EXACT
STRENGTH AND LOCATION OF THIS HIGH WILL BE A KEY PLAYER IN WHETHER
ANOTHER COASTAL LOW IMPACTS THE REGION EARLY NEXT WEEK.

FOR NOW IT APPEARS SATURDAY NIGHT AND SUNDAY SHOULD BE DRY WITH
THE REGION UNDER CONFLUENT FLOW ALOFT.

12Z ECMWF HAS TRENDED TOWARDS 12Z CMC SOLUTION OF A LOW DEVELOPING
OVER THE SE STATES SUNDAY...THEN TRACKING NE OFF THE MID-ATLANTIC
AND NE COASTS SUNDAY NIGHT-MONDAY. THE GFS HOWEVER DOES NOT SHOW
AS MUCH INTERACTION WITH A SOUTHERN PROTUBERANCE OF THE POLAR
VORTEX AND A SOUTHERN STREAM SHORTWAVE...KEEPING THE STORM WELL
TO THE S AND E. GIVEN THE OVERALL SUPERIOR PERFORMANCE OF BOTH THE
CMC AND ECMWF IN THE EXTENDED OVER THE GFS SO FAR THIS YEAR IN THE
LONG TERM...HAVE FAVORED A BLEND OF THE ECMWF/CMC FROM SUNDAY
NIGHT-TUESDAY.

BASED ON THIS BRING IN CHANCE POPS FOR MAINLY SNOW...POSSIBLY
MIXED WITH RAIN TO START ACROSS NYC AND MAYBE LONG ISLAND LATE
SUNDAY EVENING...THEN HAVE A CHANCE OF SNOW FOR ALL ZONES FROM
LATE SUNDAY NIGHT THROUGH MONDAY...WITH ONLY SLIGHT CHANCE POPS
MONDAY NIGHT AS THE STORM PULLS AWAY...AND A POTENTIAL SECONDARY
LOW LIKELY TRACKS WELL TO THE S AND E. GIVEN THE UNCERTAINTY...IT
IS TOO EARLY TO SPECULATE ON AMOUNTS OR POTENTIAL IMPACT.
REMEMBER...THERE IS STILL THE POTENTIAL THAT THE GFS COULD END UP
BEING CORRECT...AND THE AREA REMAIN DRY EARLY NEXT WEEK.

ON TUESDAY WENT DRY...WITH WEAK RIDGING FORECAST OVER THE REGION.

FOR TEMPERATURES FRIDAY NIGHT-TUESDAY USED A BLEND OF
MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE...MIXING IN ECMWF 2-METER
TEMPERATURES MONDAY-TUESDAY TO WEIGH IN EXPECTED IMPACT OF
PRECIPITATION INDUCED EVAPORATIVE COOLING AND THEN SNOW COVER.
EXPECT TEMPERATURES TO BE NEAR TO SLIGHTLY ABOVE NORMAL FRIDAY
NIGHT AND SATURDAY. THEN NEAR TO SLIGHTLY BELOW NORMAL SATURDAY
NIGHT...FOLLOWED BY BELOW NORMAL SUNDAY-TUESDAY.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
LOW PRESSURE MOVING INTO THE OHIO VALLEY WILL MOVE TOWARD THE
REGION TODAY...AND PASS DIRECTLY OVER THE REGION THIS EVENING.
A WEAK STATIONARY FRONT WILL LIFT TO THE NORTH AS A WARM FRONT
THIS MORNING. ANOTHER WARM FRONT WILL DEVELOP TO THE SOUTH
TODAY...AND LIFT INTO THE REGION JUST AHEAD OF THE LOW
TOWARD EVENING.

HAVE GONE WITH A MORE OPTIMISTIC FORECAST THROUGH AT LEAST THE
MORNING OR EARLY AFTERNOON...WITH CONTINUED VFR CONDS AND LIGHT E
FLOW VEERING SE AND INCREASING TO AROUND 10 KT THIS AFTERNOON.
CANNOT TOTALLY RULE OUR BRIEF MVFR CIGS AT SOME POINT THIS
MORNING OR EARLY AFTERNOON...BUT MVFR OR LOWER CONDS ARE MUCH MORE
LIKELY AFTER ABOUT 18Z AS THE SECOND WARM FRONT APPROACHES FROM
THE SOUTH AND RAIN BEGINS TO MOVE IN FROM THE WEST.

IFR/LIFR CONDS IN MODERATE RAIN LIKELY AT MOST SITES TOWARD
EVENING AS THE LOW APPROACHES...WITH LLWS AS S-SW FLOW AT 2 KFT
AGL INCREASES TO 45-55 KT. GUSTS IN SOUTHERLY FLOW AT KJFK/KISP
COULD END UP CLOSER TO 30 KT THIS EVENING. ISOLD-SCT TSTMS WITH
HEAVY RAIN ARE ALSO POSSIBLE FROM ABOUT 23Z-04Z AS THE SFC LOW
MOVES DIRECTLY OVER THE AREA...TOO EARLY YET FOR TAF MENTION.

AFTER THE LOW PASSES...CONDS SHOULD START TO IMPROVE TO MVFR...AND
PRECIP SHOULD CHANGE TO LIGHT SNOW BEFORE ENDING WITH LITTLE TO
NO RUNWAY ACCUMULATION EXPECTED. GUSTY NW WINDS NEAR 310 MAGNETIC
WILL ALSO DEVELOP.

.OUTLOOK FOR 06Z THU THROUGH SUNDAY...
.LATE TONIGHT...CIGS BECOMING VFR. NW WINDS NEAR OR JUST RIGHT OF
310 MAGNETIC 20-25 KT WITH GUSTS 30-35 KT.
.THU...MAINLY VFR. NW WINDS NEAR OR JUST RIGHT OF 310 MAGNETIC
20-30 KT WITH GUSTS G35-40KT.
.FRI...VFR.
.SAT...MVFR CONDS POSSIBLE IN RAIN SHOWERS.
.SUNDAY...MAINLY VFR.

&&

.MARINE...
WIND GENERALLY LIGHT AND VARIABLE ACROSS THE FORECAST WATERS.

WINDS AND SEAS INCREASE ON WED WITH SOUTHERLY FLOW. SCA CRITERIA
ARE LIKELY TO BE REACHED BY LATE AFTN.

GALE WARNING FOR WEDNESDAY NIGHT AS LOW PRESSURE PASS ACROSS LONG
ISLAND AND DEEPENS. WINDS IN THE WAKE OF THE LOW WILL QUICKLY
INCREASE FROM WEST TO EAST AROUND AND AFTER MIDNIGHT.

GALE CONDITIONS SHOULD CONTINUE INTO THURSDAY EVENING...THEN
SUBSIDE TO SMALL CRAFT LEVELS LATE THURSDAY NIGHT. SCA CONDITIONS
COULD LINGER INTO FRIDAY ON THE COASTAL OCEAN AND EASTERN WATERS.
WINDS INCREASE AHEAD OF AN APPROACHING FRONTAL SYSTEM FRIDAY
NIGHT...SO SCA LEVEL SEAS AND WINDS POSSIBLE ON COASTAL OCEAN AND
EASTERN WATERS AGAIN FRIDAY NIGHT.

SUB-SCA CONDITIONS SHOULD MOVE INTO ALL WATERS...EXCEPT FOR
POSSIBLY SEAS ON THE EASTERN COASTAL OCEAN WATERS FROM LATE
SATURDAY INTO SUNDAY.

&&

.HYDROLOGY...
A LOW PRESSURE SYSTEM WILL PASS OF THE REGION WEDNESDAY EVENING.
QPF OF AROUND 1/3 OF AN INCH ALONG THE COAST TO 3/4 OF AN INCH INLAND
IS EXPECTED. ONLY MINOR TO MODERATE RISES ARE EXPECTED ON RIVERS.

THERE IS THE POSSIBILITY OF SIGNIFICANT PRECIPITATION OVER THE
AREA FROM SUNDAY NIGHT THROUGH MONDAY. AT THIS TIME IT APPEARS IT
WILL BE MAINLY IN THE FORM OF SNOW AT THIS TIME. HOWEVER...THERE
IS STILL QUITE A BIT OF UNCERTAINTY WITH THIS SYSTEM...SO IT IS
TOO EARLY TO SPECIFY EXACT AMOUNTS OR ANY POTENTIAL IMPACT.

&&

.CLIMATE...
RECORD LOW TEMPS ARE LIKELY TO BE TIED OR BROKEN AT MOST LOCAL
CLIMATE SITES FRIDAY MORNING.

RECORD AND FORECAST LOW TEMPS FOR FRIDAY MORNING (MAR 14)...

               RECORD LOW
                MINIMUM     FCST
NEWARK.........17 IN 1980   16
BRIDGEPORT.....16 IN 1993   13
CENTRAL PARK... 8 IN 1896   18
LAGUARDIA......18 IN 1980   20
KENNEDY........19 IN 1980   18
ISLIP..........17 IN 1989   13

&&

.EQUIPMENT...
THE NOAA WEATHER RADIO TRANSMITTER THAT SERVES THE NEW YORK CITY
METROPOLITAN AREA REMAINS OUT OF SERVICE DUE TO RADIO FREQUENCY
INTERFERENCE WITH THE U.S COAST GUARD TRANSMITTER.

FOR MORE INFORMATION SEE THE FOLLOWING PUBLIC INFORMATION
STATEMENT (ALL LOWER CASE):
WWW.ERH.NOAA.GOV/OKX/PRODUCTS/STATIC.TXT

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...GALE WARNING FROM 11 PM THIS EVENING TO 2 AM EDT FRIDAY FOR
     ANZ330-335-338-340-345-350-353-355.

&&

$$

NEAR TERM...PICCA/MET
AVIATION...GOODMAN