FXUS61 KOKX 010853
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
353 AM EST TUE DEC 1 2009
.SYNOPSIS...
HIGH PRESSURE BUILDS TO THE SOUTH TODAY AND THEN EAST OF THE
AREA WEDNESDAY AFTERNOON. STRENGTHENING LOW PRESSURE OVER THE GULF
COAST STATES WILL THEN MOVE NORTHEAST TOWARD THE EASTERN GREAT LAKES
WEDNESDAY NIGHT INTO THURSDAY...WITH WINDY AND RAINY CONDITIONS
EXPECTED AS ITS TRAILING FRONTAL SYSTEM CROSSES THROUGH THE LOCAL
AREA. HIGH PRESSURE WILL RETURN LATER THURSDAY INTO FRIDAY NIGHT.
ANOTHER STORM MAY IMPACT THE AREA ON THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHORTWAVE SHEARS THROUGH NORTH OF THE REGION THIS MORNING INTO
AFTERNOON...WITH HIGH PRESSURE RIDGE SLIDING EAST OF THE REGION.
SCT-BKN STRATO-CU WITH SHORTWAVE PASSAGE...BUT SHOULD BE A MAINLY
DRY DAY WITH DEEP WESTERLY FLOW. SCATTERED SPRINKLES/FLURRIES FAR
N&W THRU THE EARLY AFTERNOON. GUSTY WSW FLOW TODAY. HIGH
GENERALLY IN THE MID TO UPPER 40S...NEAR SEASONABLE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
HIGH PRESSURE BUILDS S AND THEN SE OF THE REGION TONIGHT WITH GOOD
RADIATIONAL COOLING CONDS EXPECTED. LOW TEMPS MAINLY IN THE
30S...20S PINE BARRENS/INTERIOR VALLEYS...AROUND 40 NYC. SOME PATCHY
FOG POSSIBLE IN FAR OUTLYING AREAS.
FOR THE MOST PART MODELS IN DECENT AGREEMENT WITH BAJA LOW EJECTING
INTO THE SOUTHERN PLAINS TONIGHT...RACING TOWARDS THE NE WED NIGHT
AROUND A LARGE DIGGING MID WEST TROUGH. SHORTWAVE ENERGY REACHING
INTO W NY BY THURS MORN. GFS IS STRONGEST AND FURTHER SE OUTLIER
WITH SHORTWAVE ENERGY.
AS A RESULT...LOW PRESSURE ORGANIZING OVER THE GULF STATES WILL RACE
NE...UP THE W SIDE OF THE APPALACHIANS WED NIGHT...INTO WESTERN NY BY
THURS MORNING. GFS IS STRONGEST AND FURTHEST SE OUTLIER.
HAVE STAYED CLOSER TO FURTHER WEST AND WEAKER MODEL CONSENSUS...BETTER
CONSISTENCY.
INCREASING CLOUDS WED...LOWERING/THICKENING WED AFTERNOON IN ADVANCE
OF THE SYSTEM. OVERRUNNING LIGHT RAIN LIKELY DEVELOPING FROM SW TO NE
LATE WED AFTERNOON INTO WED EVENING...THEN MODERATE TO HEAVY RAIN
AND RISING TEMPS LIKELY WED NIGHT/EARLY THU MORNING AS A 70-80 KT
SOUTHERLY LOW LEVEL JET TRANSPORTS GULF/ATLANTIC MOISTURE NORTHWARD
AHEAD OF THE LOW AND A TRAILING COLD FRONT.
DEFINED THETA-E RIDGING WITH STRONG LLJ AND MARGINAL ELEVATED
INSTABILITY APPEARS STRONG ENOUGH FOR SOME EMBEDDED THUNDER.
WITH A 70+ LLJ AT 900 HPA...WATER TEMPS STILL IN THE LOWER 50S...AND
A TIGHT PRESSURE GRADIENT BETWEEN THE INLAND LOW AND HIGH PRESSURE
OVER THE ATLANTIC WOULD SUGGEST THE POTENTIAL FOR ADVISORY CRITERIA
WINDS (25 TO 35 MPH WITH GUSTS UP TO 50 MPH) ACROSS
NYC...COASTAL SECTIONS AND THE HIGHER ELEVATIONS LATE WED NIGHT
INTO EARLY THURS MORNING.
EXACT TIMING OF FRONT STILL TOO EARLY TO DETERMINE...BUT PRECIP
SHOULD QUICKLY TAPER OFF THURS MORN IN WAKE OF COLD FRONT AS
SHORTWAVE AND SURFACE LOW RACE NE INTO SOUTHERN QUEBEC/NORTHERN NEW
ENGLAND. AS IT APPEARS CURRENTLY...BREEZY WESTERLY FLOW...PARTIAL
CLEARING IN WAKE OF LOW...AND SLOW CAA...WILL MAKE FOR A MILD
AFTERNOON ON THURSDAY WITH EARLY HIGHS IN THE 60S...SEVERAL
DEGREES ABOVE SEASONABLE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
DECENT MODEL AGREEMENT IN THE FIRST PART OF THE LONG TERM...HOWEVER
MODEL DIFFERENCES POP UP DURING THE WEEKEND. HIGH PRESSURE BUILDS IN
BEHIND THE DEPARTING STORM THURSDAY NIGHT THROUGH AT LEAST FRIDAY.
WILL KEEP THIS PERIOD DRY. MODELS DO SHOW FALLING HEIGHTS AND
COOLING OF TEMPERATURES ALOFT...HOWEVER...COLD ADVECTION AT THE
SURFACE WILL PROBABLY BE TEMPERED TO A DEGREE BY A DOWNSLOPING
WESTERLY FLOW. HIGHS THEREFORE ON FRIDAY EXPECTED TO BE AT OR
SLIGHTLY ABOVE NORMAL.
SATURDAY IS A LOW CONFIDENCE FORECAST. H5 TROF AND SHORTWAVE
APPROACHES FROM THE WEST...WITH THE TIMING OF ITS PASSAGE DIFFERING
AMONG THE MODELS. BEST GUESS WOULD BE FOR IT TO PASS THROUGH LATE
DAY SATURDAY OR SATURDAY NIGHT. MED RANGE GUIDANCE ALL SHOW COASTAL LOW
DEVELOPMENT OFF THE SOUTHEAST COAST AND PASSING EAST OF THE 40/70
BENCHMARK. TRACK IS CLOSE ENOUGH THAT WE WILL HAVE TO KEEP AN EYE ON
THIS. WILL THEREFORE GO WITH CHC POPS ON SATURDAY AND SATURDAY
NIGHT. THERMAL PROFILES WOULD SUPPORT RAIN/SNOW MIX FOR
SATURDAY...AND TREND MORE TOWARDS SNOW SATURDAY NIGHT. HIGHS RANGING
IN THE UPPER 30S TO LOW 40S ON SATURDAY.
RIDGING THEN RETURNS AT THE SURFACE SUNDAY AND MONDAY WITH A DRY
FORECAST AND SLOWLY MODERATING TEMPERATURES.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
OCCASIONAL GUSTS NOT OUT OF THE QUESTION THROUGH 10Z...BUT FOR THE
MOST PART WINDS ARE 10 KTS ARE LESS.
GUSTS REMATERIALIZE DURING THE AFTERNOON TUESDAY. DIRECTION MAY BE
A BIT MORE TO THE RIGHT OF THE FORECASTED DIRECTIONS DURING
STRONGEST GUSTS.
SCT040 IN TAFS MAY ACTUALLY BE BKN AT TIMES THIS AFTERNOON.
OUTLOOK 00Z WEDNESDAY THROUGH SATURDAY...
TUE NIGHT-WED...VFR
WED NIGHT-THU...SUB-VFR LIKELY WITH IFR PROBABLE. LLWS POSSIBLE AS
WELL.
THU NIGHT-FRI...GUSTY NW WINDS. VFR.
FRI NIGHT...VFR WITH DIMINISHING WINDS.
SAT...VFR LIKELY WITH SUB-VFR POSSIBLE.
&&
.MARINE...
WINDS AND SEAS ON THE OCEAN STILL REACHING SCA LEVELS EARLY THIS
MORNING. EXPECT WINDS AND SEAS TO DIMINISH SLIGHTLY LATER THIS
MORNING...BUT CONDITIONS ARE EXPECTED TO REMAIN RIGHT AROUND SCA
LEVELS INTO THIS EVE. WILL LEAVE HEADLINES AS IS...BUT DAY SHIFT
WILL NEED TO MONITOR TRENDS AND COULD CANCEL THE ADVISORY EARLIER.
CONDS THEN REMAIN BELOW SCA LEVELS UNTIL WED NIGHT AS STRONG LOW
PRES LIFTS UP THE SPINE OF THE APPALACHIANS. GALES ARE A DEFINITE
POSSIBILITY INTO THU...BUT STILL TO EARLY FOR A GALE WATCH. DAY
SHIFT WILL LIKELY PUT THE WATCH UP THIS AFTN. STORM FORCE GUSTS ARE
ALSO A POSSIBILITY...PRIMARILY ON THE OCEAN WATERS...BUT IT WILL
DEPEND ON HOW INVERTED WE ARE. WILL CONTINUE TO HEADLINE GALES AND
ADD THE POSSIBILITY OF STORMS IN THE HWO.
WINDS AND SEAS WILL GRADUALLY DIMINISH THU NIGHT...WITH ALL BUT THE
OCEAN WATERS FALLING BELOW SCA LEVELS. SEAS WILL TAKE A BIT LONGER
TO SUBSIDE...THEREFORE SCA MAY BE NEEDED INTO FRI. A COASTAL STORM
PASSING TO THE EAST MAY CAUSE FLAGS TO RETURN ON SAT.
&&
.HYDROLOGY...
STRONG LOW PRESSURE COULD BRING 1-2 INCHES OF RAIN WED NIGHT INTO
THU.
STILL TOO EARLY TO SAY WHETHER ANOTHER COASTAL LOW COULD BRING
ANOTHER ROUND OF SIGNIFICANT QPF THIS WEEKEND.
&&
.TIDES/COASTAL FLOODING...
THE APPROACH OF A FULL MOON WILL KEEP ASTRONOMICAL TIDES HIGH OVER
THE NEXT SEVERAL DAYS. AN INCREASING SOUTHERLY FLOW ASSOCIATED
WITH LOW PRES PASSING TO THE WEST COULD CAUSE MINOR COASTAL
FLOODING...MAINLY IN THE SOUTH SHORE BACK BAYS OF LONG ISLAND THU
MORNING. THE STRONGEST WINDS LOOK TO OCCUR RIGHT AROUND THE TIME OF
HIGH TIDE...BUT DUE TO THE FAIRLY QUICK PROGRESSION OF THE
STORM...WINDS WILL SHIFT TO THE SW AND DECREASE SOME BY THE EVENING
HIGH TIDE CYCLE. DEPARTURES OF 1-1.5 FT ARE NEEDED TO REACH MINOR
COASTAL FLOODING LEVELS IN THE MORNING...2-2.5 FT IN THE EVENING.
MODERATE FLOODING APPEARS UNLIKELY DUE THE SHORT DURATION OF THIS
EVENT...BUT WILL STILL KEEP A CLOSE EYE ON THE MORE VULNERABLE SOUTH
SHORE BACK BAY LOCATIONS OF NASSAU COUNTY.
STORM SURGE GUIDANCE IS INDICATING THE GFS REMAINS THE STRONGEST
WITH THE SYSTEM...HENCE STRONGER WINDS AND LARGER DEPARTURES IN THE
STORM SURGE GUIDANCE. HAVE GONE MORE OF AN NAM/EC/SREF ROUTE SO NOT
TAKING THE GUIDANCE VERBATIM.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ350-353-
355.
&&
$$
SYNOPSIS...NV
NEAR TERM...NV
SHORT TERM...NV
LONG TERM...
AVIATION...BS
MARINE...AL
HYDROLOGY...NV
TIDES/COASTAL FLOODING...AL
