Area Forecast Discussion
Issued by NWS Upton, NY

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000
FXUS61 KOKX 290305
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1005 PM EST FRI NOV 28 2014

.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN FROM THE WEST OVERNIGHT...AND PASS TO
THE EAST BY SATURDAY AFTERNOON. A WARM FRONT WILL THEN APPROACH
SATURDAY AFTERNOON...MOVE SLOWLY ACROSS SATURDAY NIGHT INTO SUNDAY
NIGHT...FOLLOWED BY A COLD FRONTAL PASSAGE ON MONDAY. HIGH
PRESSURE WILL FOLLOW FOR TUESDAY...BEFORE ANOTHER FRONTAL SYSTEM
AFFECTS THE REGION TUESDAY NIGHT INTO WEDNESDAY NIGHT. HIGH
PRESSURE WILL RETURN ON THURSDAY...THEN YET ANOTHER LOW PRESSURE
SYSTEM MAY AFFECT THE REGION FOR THE END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A FEW ADJUSTMENTS MADE BASED ON STRONG RADIATIONAL COOLING
ACROSS THE INTERIOR WHERE WINDS HAVE GONE LIGHT AND VARIABLE...AND
TO ACCOUNT FOR A PERSISTENT CLOUD BAND AROUND THE RIVERHEAD AREA
OF LI. EARLIER THIS BAND HAD PRODUCED SOME FLURRIES/LIGHT SNOW
ACROSS CT. THIS AREA WILL DISSIPATE IN CONJUNCTION WITH THE NW
FLOW OVER THE NEXT SEVERAL HOURS. LOWS HAVE ALSO BEEN KNOCKED DOWN
TO 10 TO 15 DEG ACROSS ORANGE...PUTNAM...WESTERN PASSAIC...AND
NORTHERN FAIRFIELD COUNTIES. NYC METRO AND MOST OF LONG ISLAND
SHOULD SEE LOWER 20S...WITH OTHER SPOTS 15-20. MID LEVEL CLOUDS
MOVING IN LATE TONIGHT MAY ACTUALLY RESULT IN TEMPS RISING A BIT.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
INCREASING WARM AIR AND MOISTURE ADVECTION WITH THE APPROACHING
WARM FRONT SHOULD BRING MOSTLY CLOUDY SKIES...ALSO A CHANCE FOR
AFTERNOON FLURRIES AND/OR SPRINKLES ESPECIALLY NW OF NYC.
HIGH TEMPS SHOULD BE SIMILAR TO THOSE OF TODAY...MAINLY 35-40.

AS THE WARM FRONT SLOWLY LIFTS TO THE NE SAT NIGHT AT LEAST
ALOFT...CHANCES FOR FLURRIES/SPRINKLES WILL SHIFT OVER TO SOUTHERN
CT AND EASTERN LONG ISLAND. LOW LEVEL MOISTURE SHOULD HOWEVER
CONTINUE TO INCREASE...ESPECIALLY NORTH/WEST OF NYC...WHERE WEAK
TRANSIENT SHORTWAVES MAY BE ENOUGH TO HELP PRODUCE SOME PATCHY
LIGHT DRIZZLE OR FREEZING DRIZZLE NORTH/WEST OF NYC.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
MODELS IN DECENT AGREEMENT WITH THE UPPER FLOW REGIME ACROSS THE
CONUS THROUGH MONDAY...WITH ZONAL UPPER FLOW BEING INTERRUPTED BY A
COUPLE OF PIECES OF NORTHERN STREAM ENERGY DIGGING INTO THE NORTHERN
PLAINS SUN AND THEN SWINGING THROUGH SOUTHERN ONTARIO/QUEBEC THROUGH
MONDAY NIGHT. A RESULTANT LOW PRESSURE SYSTEM WILL TAKE A TRACK JUST
TO THE NORTH OF THAT...WITH ITS ASSOCIATED WARM FRONT MOVING NORTH
SUN AND THEN ITS COLD FRONT APPROACHING SUN NIGHT AND THEN CROSSING
MONDAY. FORCING IS WEAK ON SUNDAY...BUT SOUNDINGS INDICATE LOW/MID
LEVEL WAA AND SATURATION...WHICH SHOULD RESULT IN CONSIDERABLE
CLOUDINESS AND SOME PATCHY DRIZZLE AND ISOLATED SHOWER ACTIVITY SUN
THROUGH SUN NIGHT...PARTICULARLY ACROSS INTERIOR PORTIONS OF
TRI-STATE.

SURFACE COLD FRONT PASSES THROUGH MONDAY AFTERNOON WITH CAA ON GUSTY
NW WINDS IN ITS WAKE. WITH SHORTWAVE ENERGY MAKING ITS CLOSEST
APPROACH LATE MON INTO MON NIGHT AND REGION UNDER RIGHT REAR QUAD
LIFT OF STRONG UPPER JET...A LOW CHANCE FOR A PERIOD OF LIGHT
POST-FRONTAL PRECIP EXISTS BEFORE MID-LEVEL MOISTURE AXIS PUSHES
OFFSHORE LATER MON NIGHT. CMC ENSEMBLE...GEFS...AND THE 00Z/12Z
ECMWF SUPPORT THIS. ANY PRECIP SHOULD BE RAIN MON AFT...BUT THEN
CHANGING TO SNOW FROM NW TO SE BEFORE ENDING MON NIGHT. LITTLE TO
ACCUM EXPECTED AT THIS TIME. ARCTIC AIR MASS REMAIN SHUNTED WELL TO
THE NORTH...BUT TEMPS SHOULD FALL SEVERAL DEGREES BELOW NORMAL BY
TUES MORNING.

MODERATING POLAR HIGH BUILDS IN TUESDAY...WITH DRY BUT UNSEASONABLY
COLD CONDITIONS. TEMPS WILL LIKELY RUN 10 DEGREES BELOW
NORMAL...WITH HIGH GENERALLY IN THE 30S.

UNCERTAINTY IN THE FORECAST INCREASES FOR THE MID TO LATE WEEK AS
MODELS DIFFER IN THE INTERACTION OF SHORTWAVE ENERGY ROTATING AROUND
A CLOSED POLAR LOW NW OF HUDSON BAY AND ITS INTERACTION WITH
NORTHERN STREAM ENERGY. THE CMC/ECMWF AND ASSOCIATED ENSEMBLES ARE
AGGRESSIVE WITH THIS INTERACTION...PIVOTING A PHASED AND STRONG
SHORTWAVE THROUGH THE NORTHEAST WED NIGHT. THE GFS IS TAME WITH THIS
INTERACTIONS AND SIGNALING A PRACTICALLY FLAT UPPER FLOW...WHILE
THE GEFS DEPICTS A MORE AMPLIFIED SHORTWAVE PASSAGE LIKE CMC/ECMWF
ENSEMBLES. HAVE LEANED TOWARDS THE MORE AMPLIFIED FLOW AS DEPICTED
BY THE ENSEMBLE MEANS. IN TERMS OF SENSIBLE WEATHER...A RETURN FLOW
TUE NIGHT IN WAKE OF EXITING POLAR HIGH AND APPROACHING SHORTWAVE
AND ASSOCIATED FRONTAL SYSTEM...SHOULD SPELL AN INCREASING CHANCE
FOR PRECIP TUES NIGHT INTO WED. THERMAL PROFILES SUPPORT WINTRY
PRECIP TO START TUE NIGHT...THEN GRADUALLY CHANGING TO RAIN FROM S
TO N ON WED. COLD AIR DAMMING COULD MAKE FZRA STUBBORN ACROSS
INTERIOR TRI-STATE ON WED. THIS SYSTEM SHOULD EXIT WED NIGHT AS THE
SHORTWAVE AXIS PIVOTS THROUGH...WITH ANOTHER GLANCING SHOT OF CAA IN
ITS WAKE.

MODERATED POLAR HIGH PRESSURE LIKELY BUILDS IN ON THURSDAY WITH DRY
AND BELOW SEASONABLE TEMPS.

MODEL IN GOOD AGREEMENT WITH A PAC SHORTWAVE AND ASSOCIATED QUICK
MOVING LOW PRESSURE APPROACHING LATE WEEK...BUT TIMING INTO REGION
DIFFERS FROM THU INTO FRI BASED ON ABOVE MENTIONED DIFFERENCES WITH
THE PRIOR NORTHERN STREAM SHORTWAVE. HAVING FAVORED MORE AMPLIFIED
AND SLOWER PATTERN...HAVE DELAYED CHANCE POPS WITH THE NEXT
SHORTWAVE UNTIL FRIDAY.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL CONTINUE TO BUILD IN THROUGH TONIGHT.

VFR. NW WINDS RIGHT AROUND 310 MAGNETIC EARLY THIS EVENING BEFORE
WINDS BECOME LIGHT AND VARIABLE LATE AS RIDGE AXIS MOVES OVERHEAD.

MID LEVEL WARM ADVECTION CLOUDS MOVE IN AFTER 06Z AND REMAIN
THROUGH SAT. POSSIBLE MVFR CIGS AFTER 00Z FOR 30H TAFS.

.OUTLOOK FOR 00Z SUN THROUGH WED...
.SAT NIGHT-SUN...PATCHY DRIZZLE AND MVFR CONDS ACROSS THE LOWER
HUDSON VALLEY...OTHERWISE VFR.
.SUN NIGHT-MON...MVFR CONDS POSSIBLE. SOME PATCHY DRIZZLE LATE
SUNDAY NIGHT AT KSWF...OTHERWISE CHANCE OF RAIN SHOWERS.
.TUE...VFR.
.WED...CHANCE OF RAIN WITH MVFR OR LOWER CONDS.

&&

.MARINE...
SCA HAS BEEN DISCONTINUED ACROSS THE OCEAN WATERS TONIGHT.

INCREASING SW FLOW SHOULD RESULT IN ANOTHER PD OF SCA CONDS ON THE
OCEAN AND POSSIBLY THE ERN SOUND/BAYS SAT NIGHT.

SCA OCEAN SEAS ARE LIKELY ON SUNDAY...WITH MARGINAL SW SCA WINDS
CONTINUING. SSW SCA SWELLS COULD LINGER ON THE OCEAN...
PARTICULARLY EAST...INTO MON AFTERNOON. SCA SEAS COULD CONTINUE
INTO MON NIGHT WITH A PERIOD OF MARGINAL NW SCA GUSTS POSSIBLE
IN WAKE OF A MON AFTERNOON COLD FRONTAL PASSAGE.

SUB SCA CONDS THEN EXPECTED BY TUE AS HIGH PRESSURE BUILDS OVER
THE WATERS...WITH NEXT CHANCE OF MARGINAL SCA CONDS POSSIBLE ON
THE OCEAN WATERS LATE TUE NIGHT INTO WED WITH NEXT FRONTAL SYSTEM.

&&

.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...GOODMAN/NV
NEAR TERM...GOODMAN/DW
SHORT TERM...GOODMAN
LONG TERM...NV
AVIATION...DW
MARINE...GOODMAN/NV/DW
HYDROLOGY...GOODMAN/NV





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