Area Forecast Discussion
Issued by NWS Upton, NY

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000
FXUS61 KOKX 280001
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
701 PM EST THU NOV 27 2014

.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL MOVE ACROSS THE AREA TONIGHT FOLLOWED
BY HIGH PRESSURE FRIDAY THROUGH SATURDAY. A WARM FRONT WILL MOVE
NORTHEAST ACROSS THE AREA FOLLOWED BY A COLD FRONT MONDAY. HIGH PRESSURE
FOLLOWS TUESDAY AND WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
WEAK RADAR RETURNS ACROSS COASTAL CT AND EASTERN LI SUPPORTING
SOME LIGHT SNOW AND/OR RAIN. OBS ACROSS CT SUPPORT A VERY LIGHT
SNOW WITH LITTLE TO NO ACCUMULATION. TEMPS GENERALLY IN THE MID TO
UPPER 30S. DUE TO DRY MID LEVELS AND LACK OF ICE NUCLEI...SOME OF
THIS COULD FALL AS LIGHT RAIN OR SPRINKLES. SHORT WAVE TROF ACROSS
WESTERN PA SEEMS TO BE FOCUSING ADDITIONAL SNOW SHOWER ACTIVITY.
OFTEN THIS TYPE OF ACTIVITY DOES NOT MAKE IT EAST OF THE RIDGES.
WILL MAINTAIN SLIGHT CHC POPS FOR SNOW SHOWERS OVERNIGHT. A MORE
SIGNIFICANT TROWAL EVENT COULD OCCUR ACROSS CAPE COD OVERNIGHT.


TONIGHT...CLOUDS WILL REMAIN IN PLACE AS LOW PRES DEVELOPS OFF THE NC
COAST AND MOVES NE. MODELS SHOW THE DEVELOPMENT OF AN INVERTED TROUGH
DEVELOPING NW FROM THIS LOW TOWARD SE NEW ENGLAND. THIS LOW LVL
CONVERGENCE COULD PRODUCE SOME LIGHT SNOW ACROSS LONG ISLAND AND
CT DEPENDING ON WHERE IT DEVELOPS. IN ADDITION...ANOTHER UPPER LVL
TROUGH APPROACHING FROM THE GREAT LAKES COULD PRODUCE SOME LIGHT
SNOW SHOWERS OVER AND WEST OF NYC...WHICH IS WHY A 20 PCT POP WAS
INCLUDED AREA WIDE.

MELTED SNOW WILL RE-FREEZE OVERNIGHT AS TEMPERATURES FALL MAINLY INTO
THE 20S EXCEPT RIGHT AROUND 30 DEGS IN NYC.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRIDAY...A COLD CANADIAN HIGH PRES SYS WILL FOLLOW THE PASSAGE OF THE
UPPER LVL TROUGH BRINGING A REINFORCING SURGE OF COLD AIR. NORTHWEST
WINDS OF 10-20 MPH WILL BRING WIND CHILLS DOWN INTO THE TEENS AND 20S
TO START THE DAY BEFORE RISING INTO THE 30S DURING THE AFTERNOON. ANOTHER
COLD DAY IS ON TAP WITH TEMPS AVERAGING ARND 10 DEGS BELOW NORMAL.

FRIDAY NIGHT...STRONG RADIATIONAL COOLING WILL RESULT AS SFC WINDS
DECOUPLE FROM THE UPPER FLOW AS HIGH PRES PASSES OVERHEAD. LOWS
ARE FORECAST TO DIP INTO THE TEENS AND 20S AREA WIDE.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
A ZONAL FLOW WILL DEVELOP THIS WEEKEND WITH SEVERAL FAST MOVING
FRONTAL SYSTEMS TO IMPACT THE AREA THROUGH THE UPCOMING WEEK. PAC
SHORT WAVE ENERGY WILL PHASE WITH POLAR JET ENERGY WITH A COLD
FRONTAL PASSAGE LATE MON...AND ANOTHER WED AFT/EVE. LIGHT TO
MODERATE WARM ADVECTION PCPN PRECEDES EACH SYSTEM WITH A BRIEF MIX
OF FROZEN PCPN AT THE ONSET POSSIBLE ACROSS THE INTERIOR BEFORE
THERMO PROFILES WARM. SUN MORNING AND TUE NIGHT ARE THE TIMES OF
INTEREST. THE LATTER IS POTENTIALLY THE MORE SIGNIFICANT OF THE TWO
AS IT PRECEDED BY A TRANSIENT 1045 MB HIGH MOVING ACROSS NEW
ENGLAND. WARM SECTOR RAIN OR SHOWERS WILL PRECEDE EACH COLD
FRONT.

FOR THE MOST PART...LOOKING AT SLIGHTLY ABOVE NORMAL TEMPS THROUGH
THE PERIOD DUE TO THE PROGRESSIVE FLOW...THE EXCEPTION BEING SAT AT
THE START OF THE PERIOD WITH RESIDUAL COLD AIR IN PLACE...AND TUE
FOLLOWING THE MON COLD FRONTAL PASSAGE.

THE 12Z GFS AND ECMWF ARE IN CLOSE AGREEMENT WITH SMALL TIMING
DIFFERENCES WITH THE FRONTAL SYSTEMS. THE ECMWF IS ALSO MORE
AMPLIFIED WITH THE UPPER TROF MOVING ACROSS EASTERN CANADA AND THE
NE ON WED. THUS...IT IS MORE AGGRESSIVE WITH THE WARM ADVECTION AND
AMOUNT OF QPF.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
A HIGH PRES RIDGE BUILDS IN THRU FRI.

MAINLY VFR IN THE CITY...WITH MVFR ACROSS THE HUDSON VALLEY AND
INTO ERN CT. KSWF MAY REMAIN DOWN ALL NGT DUE TO WEAK MOIST
FLOW...THE REST OF THE REGION IS EXPECTED TO IMPROVE TO VFR BY
6-7Z.

VFR FRI AND FRI NGT.

NW WINDS BLW 10 KT TNGT...THEN GUSTS UP TO 20 KT FRI.

.OUTLOOK FOR 00Z SAT THROUGH TUE...
.FRI NGT-SUN...VFR.
.SUN NIGHT-MON...MVFR POSSIBLE WITH A CHANCE OF RAIN SHOWERS.
.TUE...VFR.

&&

.MARINE...
SEVERAL NEAR AND SHORT TERM FORECAST CHANGES WERE MADE.

ALL SMALL CRAFT ADVISORIES WERE CANCELLED THROUGH TONIGHT FOR THE
ATLANTIC OCEAN COASTAL WATERS EXCEPT FROM MORICHES INLET TO MONTAUK
PT...WHERE THEY WERE EXTENDED UNTIL MIDNIGHT SAT.

SMALL CRAFT ADVISORIES WERE ISSUED FOR WIND GUSTS OF 25 KT...
6 AM - 7 PM FRI FROM SANDY HOOK NJ TO FIRE ISLAND INLET NY
6 AM - MIDNIGHT SAT FROM FIRE ISLAND INLET EAST TO MONTAUK
PT...EASTERN LONG ISLAND SOUND AND GARDINERS AND PECONIC BAYS

ANOTHER SURGE OF COLD AIR IS FORECAST TO PRODUCE NW WINDS OF 15-25
KT BY SUNRISE FRIDAY.

WINDS AND SEAS WILL SUBSIDE...ESPECIALLY AFTER MIDNIGHT SATURDAY
AS HIGH PRESSURE PASSES OVER THE COASTAL WATERS.

OCEAN SEAS/WINDS COULD AGAIN REACH MARGINAL SCA LEVELS SAT NIGHT
INTO SUNDAY NIGHT VIA A MODERATE SW FLOW. SCA SEAS MAY LINGER ON
THE OCEAN INTO MON. SUB-SCA CONDITIONS ARE FORECAST FROM MON NIGHT
INTO TUE.

&&

.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS FORECAST DURING THE NEXT 7 DAYS.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO MIDNIGHT EST FRIDAY
     NIGHT FOR ANZ330-340-353.
     SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST FRIDAY FOR ANZ355.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST FRIDAY NIGHT FOR
     ANZ350.

&&

$$

SYNOPSIS...GC
NEAR TERM...GC/DW
SHORT TERM...GC
LONG TERM...DW
AVIATION...JMC
MARINE...GC/DW
HYDROLOGY...GC/DW







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