Area Forecast Discussion
Issued by NWS Upton, NY

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000
FXUS61 KOKX 110010
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
710 PM EST WED FEB 10 2016

.SYNOPSIS...
LOW PRESSURE EAST OF NEW ENGLAND THIS EVENING WILL GRADUALLY LIFT
NORTHEAST ACROSS THE CANADIAN MARITIMES THROUGH THURSDAY...WHILE
POLAR HIGH PRESSURE BUILDS EAST FROM THE MIDWEST. A WEAK TROUGH OF
LOW PRESSURE WILL PASS THROUGH THE AREA THURSDAY AFTERNOON. A
STRONG ARCTIC COLD FRONT WILL THEN APPROACH FRIDAY NIGHT AND PASS
THROUGH SATURDAY MORNING AS A DEVELOPING OCEAN STORM PASSES BY TO
THE SOUTHEAST. STRONG ARCTIC HIGH PRESSURE WILL BUILD ACROSS LATER
SATURDAY INTO SUNDAY NIGHT...THEN RETREAT TO THE NORTHEAST MONDAY
INTO MONDAY NIGHT. A LOW PRESSURE SYSTEM FOLLOWS FOR THE MID-WEEK
PERIOD.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
MINOR ADJUSTMENTS MADE TO FORECAST BASED ON CURRENT CONDITIONS.
LIGHT SNOW IS FALLING ACROSS WESTERN PA IN ASSOC WITH THE THE
APPROACHING UPPER TROUGH. THERE IS SOME UNCERTAINTY AS TO HOW
MUCH OF THIS ACTIVITY WILL MAKE IT EAST OF THE RIDGES LATER
TONIGHT WITH A MODERATE WESTERLY.

SHORT WAVE RIDGING ALOFT WILL BRIEFLY BUILD ACROSS THE AREA THIS
EVENING WHICH WILL RESULT IN PARTIAL CLEARING. THE UPPER TROUGH
AXIS TO THE WEST THOUGH WILL APPROACH LATER TONIGHT WITH DECENT
LIFT IN THE LOW TO MID LEVELS AND A NEARLY SATURATED 850-700 MB
LAYER. THIS SHOULD PRODUCE SCT SNOW SHOWERS AND/OR FLURRIES
ACROSS THE REGION DURING THE OVERNIGHT. A DUSTING IS POSSIBLE
ACROSS THE REGION.

GRADUAL COLD ADVECTION WILL CONTINUE THROUGH THE NIGHT WITH THE
UPPER TROUGH MOVING ACROSS THE AREA. OVERNIGHT LOWS WILL BE IN
THE UPPER TEENS TO THE LOWER 20S. WIND CHILL VALUES WILL DROP TO
AROUND 10.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
UPPER TROUGH AXIS LIFTS NE ACROSS THE REGION ON THU AND PASSES TO
THE NE BY EVENING. DEEP-LAYERED CYCLONIC FLOW AND STEEP MID-
LEVEL LAPSE RATES WILL RESULT IN SCT SNOW SHOWERS THROUGH THE DAY.
THE MOST LIKELY TIME WOULD BE DURING THE LATE MORNING AND
AFTERNOON WHEN SFC BASED INSTABILITY IS THE GREATEST.

A TIGHT PRESSURE GRADIENT BETWEEN DEPARTING LOW PRESSURE OVER THE
CANADIAN MARITIMES AND HIGH PRESSURE BUILDING EAST FROM THE
MIDWEST WILL RESULT IN WIND GUSTS UP TO 30 MPH...POSSIBLY HIGHER
DURING THE EARLY EVENING HOURS WITH THE PASSAGE OF A SFC TROUGH.
COLD ADVECTION WILL CONTINUE WITH 85H TEMPS APPROACHING -20 DEG C
BY EVENING. WINDS BEGIN TO RELAX LATE THU NIGHT AS HIGH PRESSURE
BUILDS OVER THE MID ATLANTIC STATES. SKIES WILL CLEAR THU EVENING.

HIGHS THU WILL BE 25 TO 30...AND LOWS THU NIGHT WILL BE IN THE
SINGLE DIGITS INLAND AND IN THE LOWER TO MID TEENS AT THE COAST.
THESE READINGS WILL BE 10-15 DEGREES BELOW NORMAL.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
FRIDAY BEGINS WITH FAIR CONDITIONS WITH WEAK SURFACE RIDGING AND A
ZONAL FLOW ALOFT. THE ATMOSPHERIC COLUMN BEGINS TO MOISTEN ALOFT
AHEAD OF SHORTWAVE ENERGY ROUNDING THE PERIPHERY OF A DEEP UPPER
TROUGH/POLAR VORTEX. WITH THE LACK OF COMBINED LIFT AND SUFFICIENT
MOISTURE...WILL GO WITH A DRY FORECAST. A MAV/NAM MOS BLEND LOOKED
GOOD FOR HIGH TEMPS...WHICH WILL BE BELOW NORMAL.

AN ARCTIC COLD FRONT THEN APPROACHES FRIDAY NIGHT ALONG WITH THE
SHORTWAVE FROM THE NORTH. AT THE SAME TIME...SHORTWAVE ENERGY MOVES
OFF THE MID ATLANTIC COAST. THE COMBINED ENERGY SHOULD INITIATE SFC
CYCLOGENESIS ALONG A BAROCLINIC ZONE TO OUR SOUTH WITH THE LOW
PASSING WELL SE OF THE 40N/70W BENCHMARK LATE AT NIGHT. LOOKS LIKE
ANY CHANCE OF SNOW DIRECTLY ASSOCIATED WITH THIS LOW LOOKS
LOW...HOWEVER...WITH THE ARCTIC FRONT AND DECREASING STABILITY DUE
TO CYCLONIC FLOW ALOFT...SCT SNOW SHOWERS EXPECTED. WILL CAP POPS AT
CHC FOR NOW.

AN ANOMALOUSLY COLD AIR MASS THEN POURS IN BEHIND THE COLD FRONT FOR
THE WEEKEND. ANOTHER SHORTWAVE ARRIVES ALONGSIDE THE CORE OF COLD
AIR ALOFT DURING SAT/SAT EVENING. THE ATMOSPHERIC COLUMN
DRIES...HOWEVER THERE IS STILL AT LEAST A CHANCE OF FLURRIES DURING
THIS PERIOD.

AS FOR TEMPS SAT AND SAT NIGHT...THE CALENDAR DAY HIGH TEMP ON
SATURDAY WILL PROBABLY OCCUR DURING THE PRE-DAWN HOURS AS STRONG
COLD ADVECTION DROPS TEMPS THROUGHOUT THE DAY. BY NOON...TEMPS
ARE PROBABLY IN THE TEENS AREA-WIDE WITH WIND CHILL VALUES BELOW
ZERO. RECORD TO NEAR-RECORD COLD TEMPS FOR SAT NIGHT IN SPITE OF
GUSTY NW FLOW. BOTH GFS AND ECMWF SHOW 850MB TEMPS DROPPING TO -29C
TO -30C DURING THE NIGHT BEFORE RISING A FEW DEGREES TOWARD
DAYBREAK. BASED ON TEMPS THAT OCCURRED DURING A SIMILAR SYNOPTIC
SETUP LAST FEBRUARY WITH WARMER TEMPS ALOFT...WENT SLIGHTLY BELOW
THE LOW TEMPS THAT HAD OCCURRED...WHICH ARE CLOSE TO WHAT ECMWF MOS
HAS BEEN SHOWING FOR THE PAST FEW RUNS. SEE THE CLIMATE SECTION
BELOW FOR MORE DETAILS. THE COLD AIR COMBINED WITH WINDS WOULD
PRODUCE WIND CHILLS THAT WOULD WARRANT AN ADVISORY DURING SAT NIGHT
INTO SUNDAY MORNING...POSSIBLY EVEN A WARNING FOR SOME OF THE
NORTHERN SUBURBS.

REMAINING COLD BUT DRY ON SUNDAY AS HIGH PRESSURE BUILDS IN WITH
HIGHS ONLY IN THE TEENS. MODELS THEN IN DISAGREEMENT WITH THE TIMING
OF THE NEXT SYSTEM TO POTENTIALLY AFFECT THE REGION. HIGH PRESSURE
SHIFTS OFFSHORE ON MONDAY WITH THE LIKELIHOOD THAT THE DAYTIME HOURS
REMAIN DRY. A LONGWAVE TROUGH THEN SHIFTS THROUGH THE EASTERN HALF
OF THE U.S. WITH ITS AXIS PROGGED TO MOVE THROUGH DURING TUESDAY
NIGHT. THIS THEN HELPS STRENGTHEN A SURFACE LOW MOVING UP THE
VICINITY OF THE EASTERN SEABOARD. LOW CONFIDENCE IN THE
EVOLUTION...TRACK AND TIMING OF THIS SYSTEM...AND CONSEQUENTLY PCPN
TYPE. HAVE CAPPED POPS AT 50 PERCENT FOR THE REST OF THE LONG TERM
FORECAST FOR THE TIME BEING AND WENT WITH A GENERAL RAIN...SNOW OR
MIX OF THE TWO AS PCPN TYPE.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
MAINLY VFR ACROSS THE TERMINALS. WEAK TROUGH PASSES THROUGH THE
REGION LATE TONIGHT AND INTO THURSDAY MORNING...POSSIBLY TOUCHING
OFF SOME LIGHT SNOW SHOWERS AND/OR FLURRIES WITH BRIEF MVFR CONDS
AROUND DAYBREAK THURSDAY. HOWEVER...PROBABILITIES ARE TOO LOW TO
INCLUDE IN THE TAFS

PRES GRADIENT TIGHTENS OVERNIGHT WITH WINDS/GUSTS INCREASING
BETWEEN 06Z AND 12Z...AND STRENGTHEN FURTHER BETWEEN 12Z AND 18Z.

 ...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: GUSTS MAY BECOME OCNL UNTIL LATE TONIGHT.
TIMING OF 30 KT GUSTS MAY BE +/- 1-2 HOURS.

KLGA FCSTER COMMENTS: GUSTS MAY BECOME OCNL UNTIL LATE TONIGHT.
TIMING OF 30 KT GUSTS MAY BE +/- 1-2 HOURS.

KEWR FCSTER COMMENTS: GUSTS MAY BECOME OCNL UNTIL LATE TONIGHT.
TIMING OF 30 KT GUSTS MAY BE +/- 1-2 HOURS.

KTEB FCSTER COMMENTS: NO UNSCHEDULED AMDS EXPECTED.

KHPN FCSTER COMMENTS: NO UNSCHEDULED AMDS EXPECTED.

KISP FCSTER COMMENTS: NO UNSCHEDULED AMDS EXPECTED.

.OUTLOOK FOR 00Z THURSDAY THROUGH MONDAY...
.THURSDAY NIGHT...VFR. DIMINISHING NW WINDS.
.FRIDAY...VFR.
.SATURDAY...SUB-VFR POSSIBLE IN BRIEF -SHSN. NW WINDS AROUND 20 KT
WITH GUSTS UP TO 30 KT.
.SUNDAY-MONDAY...VFR.

&&

.MARINE...
A GALE WARNING IS UP FOR THE OCEAN WATERS WITH A SCA ELSEWHERE
FOR STRENGTHENING W/NW WINDS TONIGHT INTO THU NIGHT. LOW PRESSURE
EAST OF NEW ENGLAND THIS EVE WILL TRACK NE ACROSS THE CANADIAN
MARITIMES THROUGH THU NIGHT...WHILE HIGH PRESSURE BUILDS EAST FROM
THE MIDWEST. THIS WILL PRODUCE A STRONG GRADIENT WIND. IN
ADDITION...COLD AIR ACROSS THE RELATIVELY WARM WATERS WILL ALLOW
MIXING OF GALE FORCE GUSTS DOWN TO THE OCEAN SFC.

LINGERING SCA CONDS ARE POSSIBLE FRI MORNING ON THE OCEAN WATERS.
WINDS AND SEAS OTHERWISE SUBSIDE FOR A BRIEF PERIOD OF SUB-SCA
CONDS. WINDS AND SEAS THEN PICK UP AGAIN FRIDAY NIGHT AHEAD OF A
COLD FRONT WHICH IS EXPECTED TO PASS THROUGH LATE AT NIGHT INTO
SATURDAY MORNING. AFTER ITS PASSAGE...STRONG COLD AIR ADVECTION
AND A TIGHT PRESSURE GRADIENT ARE EXPECTED TO BRING GALE FORCE
WINDS TO MOST IF NOT ALL WATERS. GALES COULD LAST INTO SATURDAY
EVENING FOR THE OCEAN AND EASTERN WATERS...OTHERWISE...WINDS
GRADUALLY DIMINISH THROUGH THE NIGHT INTO SUNDAY. SCA CONDS ALL
WATERS ON SUNDAY SHOULD QUIET DOWN AGAIN SUNDAY NIGHT AS STRONG
HIGH PRESSURE BUILDS OVERHEAD. THE HIGH SHIFTS OFFSHORE ON MONDAY
WITH INCREASING WINDS AND SEAS...BUT PROBABLY REMAINING BELOW SCA
CRITERIA AT LEAST DURING THE DAYTIME.

&&

.HYDROLOGY...
SCT SNOW SHOWERS LATE TONIGHT THROUGH SAT WILL RESULT LIQUID
EQUIVALENTS OF LESS THAN A TENTH OF AN INCH.

A LOW PRESSURE SYSTEM IMPACTING THE AREA FROM MON NIGHT THROUGH TUES
NIGHT COULD BRING A LIQUID EQUIVALENT PCPN AMOUNT OF AN INCH OR GREATER.
PRIMARY PCPN TYPE IS UNCERTAIN...SO WILL NEED TO MONITOR THIS SYSTEM
FOR POTENTIAL ADVERSE HYDROLOGIC IMPACTS.

&&

.CLIMATE...
WITH THE EXTREMELY COLD AIR MASS FORECAST SATURDAY INTO
SUNDAY...RECORD MINIMUMS AND RECORD LOW MAXIMUMS MAY BE REACHED.
HERE ARE THE RECORDS AND FORECASTS...

STATION......RECORD/FCST MINIMUM...RECORD LOW MAXIMUM/FCST HIGH
                 FOR 2/14                    FOR 2/14

NYC...........2 (1916)  /  1.............17 (1979) / 19
LGA...........1 (1979)  /  2.............15 (1979) / 19
JFK...........4 (1979)  /  2.............17 (1979) / 19
ISP...........7 (2015)  /  1.............26 (1987) / 18
EWR...........0 (1979)  /  0.............15 (1979) / 19
BDR...........3 (2015*) /  0.............18 (1979) / 17

*IN 1979 AS WELL

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM THURSDAY TO 6 AM EST FRIDAY FOR
     ANZ330-335-338-340-345.
     SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ350-353-
     355.
     GALE WARNING FROM 6 AM THURSDAY TO 1 AM EST FRIDAY FOR ANZ350-
     353-355.

&&

$$

SYNOPSIS...JC/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...JC
AVIATION...24
MARINE...JC/DW
HYDROLOGY...JC/DW
CLIMATE...//


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