FXUS61 KBUF 092003
AFDBUF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
303 PM EST WED DEC 9 2009
.SYNOPSIS...
AN INTENSE AREA OF LOW PRESSURE CENTERED OVER LAKE HURON THIS
AFTERNOON WILL TRACK NORTHEAST TO THE CANADIAN MARITIMES BY THURSDAY
AFTERNOON. THIS WILL RESULT IN THE DEVELOPMENT OF HIGH WINDS ACROSS
THE REGION WITH WIND DRIVEN LAKE EFFECT SNOWS DEVELOPING TONIGHT AND
CONTINUING INTO AT LEAST FRIDAY. VERY HEAVY LAKE EFFECT SNOWS WILL
BE FOUND IN THE TRADITIONAL SNOWBELT AREAS EAST OF BOTH LAKES ERIE
AND ONTARIO.
&&
.NEAR TERM /THROUGH THURSDAY/...
975MB LOW CENTERED OVER NORTHERN LOWER MICHIGAN AT 19Z. FROM A
SYNOPTIC STANDPOINT...SHORT TERM MODELS IN GOOD AGREEMENT IN TAKING
THIS LOW ACROSS LAKE HURON AND GEORGIAN BAY THIS EVENING THEN MOVING
INTO WESTERN QUEBEC BY THURSDAY MORNING...WITH A SECONDARY TRIPLE
POINT/COASTAL REDEVELOPMENT OVER THE GULF OF SAINT LAWRENCE BY
THURSDAY AFTERNOON. A POWERFUL COLD FRONT TRAILING THIS LOW WILL
SURGE ACROSS THE CWA THROUGH THE MID TO LATE AFTERNOON...REACHING
THE EASTERN LAKE ONTARIO REGION BEFORE 00Z THURSDAY.
LOTS OF HIGH IMPACT WEATHER TO TALK ABOUT...HERE IS THE BREAKDOWN.
WINDS...
THE WIND WILL SHIFT QUICKLY TO THE SOUTHWEST WITH THE COLD
FRONTAL PASSAGE THROUGH THE AFTERNOON. MAY GET A QUICK BURST OF
STRONG WINDS ALONG AND JUST BEHIND THE FRONT. MAY ALSO CONTINUE TO
SEE ISOLATED TO SCATTERED CONVECTION ALONG THE FRONT...WITH LINE
SEGMENTS POTENTIALLY LEADING TO AN ISOLATED DAMAGING WIND REPORT.
THE MAIN EVENT WILL BE SYNOPTICALLY DRIVEN GRADIENT WINDS IN THE
STRONG COLD AIR ADVECTION BEHIND THE FRONT. 925MB WINDS PEAK AT
AROUND 50 KNOTS TONIGHT...AND MOST OF THIS WILL BE ABLE TO MIX DOWN
IN THE FORM OF GUSTS WITH STRONG DOWNWARD MOMENTUM TRANSFER IN THE
COLD AIR ADVECTION/PRESSURE RISE REGIME. EXPECT SUSTAINED WINDS IN
THE 25-35 MPH RANGE WITH GUSTS TO 60 MPH. MAY EVEN SEE SOME GUSTS
PUSHING OVER 60 MPH ALONG THE LAKE ERIE SHORE. EXPECT THE STRONGEST
WINDS TO BE FROM THE NIAGARA FRONTIER TO ROCHESTER...AND ALSO
NORTHEAST OF LAKE ONTARIO. THAT SAID...AREAS FROM THE INTERIOR
SOUTHERN TIER THROUGH THE NORTHERN FINGER LAKES SHOULD GUST TO 50-55
MPH WITH ISOLATED DAMAGE POSSIBLE. WILL THEREFORE KEEP THE HIGH WIND
WARNING FOR THE ENTIRE CWA.
EXPECT THE WORST OF THE WINDS TO COME TONIGHT...BUT STRONG WINDS
WILL CONTINUE DURING THE DAY THURSDAY WITH GUSTS IN THE 50-55 MPH
RANGE CONTINUING. FOR NOW WILL KEEP THE HIGH WIND WARNING GOING
THROUGH EARLY THURSDAY EVENING.
SYNOPTIC SNOWFALL...
EXPECT RAIN TO QUICKLY CHANGE TO SNOW SHOWERS FROM WEST TO EAST THIS
EVENING. OUTSIDE OF LAKE EFFECT AREAS...SNOWFALL AMOUNTS SHOULD BE
MINIMAL WITH AN INCH OR LESS TONIGHT FROM THE INTERIOR SOUTHERN TIER
INTO THE WESTERN AND NORTHERN FINGER LAKES. GIVEN THE VERY MEAGER
SNOWFALL AMOUNTS...SHOULD BE ABLE TO GET AWAY WITH NO WINTER WEATHER
HEADLINES IN THESE AREAS. ON THURSDAY JUST EXPECT SCATTERED LIGHT
SNOW SHOWERS WITH LESS THAN AN INCH OUTSIDE OF LAKE EFFECT AREAS.
THE SNOW SHOWERS MAY BE MORE CONCENTRATED UP IN THE NORTH COUNTRY
WHERE AN INCH OR TWO MAY ACCUMULATE.
LAKE EFFECT...
OFF LAKE ERIE...
AIRMASS QUICKLY COOLS WITH 850MB TEMPS DROPPING TO AROUND -6C BY 00Z
THURSDAY THEN TO ABOUT -12C BY 12Z. WINDS INITIALLY ABOUT 220-230
DEGREES LATER THIS EVENING WILL SET UP THE BAND INITIALLY OVER THE
BUFFALO NORTHTOWNS AND SOUTHERN NIAGARA/ORLEANS COUNTIES. THE BAND
WILL THEN SHIFT SOUTH OVERNIGHT TO A 240 FLOW BY 12Z THURSDAY. BY
12Z THURSDAY...EXPECT 2-5 INCHES OVER PORTIONS OF NIAGARA AND
ORLEANS COUNTIES...WITH 3-6 POSSIBLE ACROSS THE BUFFALO METRO AREA
TO GENESEE COUNTY. STRONG WINDS AND AN UNSTABLE BOUNDARY LAYER WILL
ALLOW DEEP INLAND PENETRATION...WITH A FEW INCHES POSSIBLE ALL THE
WAY INTO THE ROCHESTER AREA.
DURING THE DAY THURSDAY EXPECT THE BAND TO SETTLE INTO A 240-250
DEGREE CONFIGURATION. THIS WILL TARGET THE SOUTHERN HALF OF THE
BUFFALO METRO AREA INTO CENTRAL AND SOUTHERN GENESEE COUNTY AS WELL
AS SOUTHERN ERIE/WYOMING COUNTIES. MESOSCALE MODELS ALSO SUGGEST THE
BAND WILL BE HUGGING THE LAKE ERIE SHORE...IMPACTING WESTERN
PORTIONS OF CHAUTAUQUA COUNTY AND EXTREME NORTHWEST CATTARAUGUS
COUNTY. WILL GO WITH ADDITIONAL ACCUMS OF AROUND A FOOT ACROSS THE
BUFFALO SOUTHTOWNS EAST TO SOUTHERN GENESEE AND SOUTHERN WYOMING
COUNTIES. AMOUNTS WILL DROP OFF ON EITHER SIDE OF THIS AXIS. IN THE
BUFFALO METRO AREA...EXPECT A WIDE RANGE FROM A FOOT IN THE
SOUTHTOWNS TO ONLY AN INCH OR TWO IN THE NORTHTOWNS. 6-10 INCHES
POSSIBLE OVER WESTERN CHAUTAUQUA AND EXTREME NORTHWEST CATTARAUGUS
COUNTIES...BUT THIS IS SOMEWHAT LOWER CONFIDENCE WITH THE BAND JUST
BARELY EDGING INTO THESE AREAS. THE STRONG WINDS MAY TEND TO SPREAD
THE LAKE EFFECT OUT INTO A LARGER FOOTPRINT THAN NORMAL...WITH
SEVERAL BANDS POSSIBLE INSTEAD OF ONE INTENSE BAND.
OFF LAKE ONTARIO...
EXPECT A BAND TO INITIALLY FORM AFTER MIDNIGHT NORTH OF WATERTOWN
THROUGH THE THOUSAND ISLANDS REGION...THEN SINK SOUTH INTO THE
WATERTOWN AREA BY MORNING. WILL GO WITH ACCUMS OF ONLY 1-3 INCHES BY
MORNING WITH THE BETTER ORGANIZATION EXPECTED AFTER 12Z IN THIS
AREA. DURING THE DAY THURSDAY...EXPECT THE BAND TO BECOME STEADY
STATE ON A 240-250 FLOW...WHICH TARGETS THE WATERTOWN AREA EAST TO
NORTHERN LEWIS COUNTY. WE TYPICALLY ALSO SEE UPSLOPE BRING HEAVY
SNOW FARTHER SOUTH DOWN THE CREST OF THE TUG HILL...EVEN THOUGH THE
FLOW DIRECTION DOES NOT NECESSARILY FAVOR THESE AREAS JUST YET. WILL
GO WITH ADDITIONAL 8-10 INCH AMOUNTS FROM NEAR WATERTOWN EAST TO
CROGHAN AND HARRISVILLE...AND ALSO SOUTHWARD DOWN THE TUG. ALSO
CLIPPED EXTREME NORTHEAST OSWEGO COUNTY WITH ABOUT 6 INCHES IN
REDFIELD DUE TO UPSLOPING.
BLOWING/DRIFTING SNOW...
WITH WINDS OF THESE MAGNITUDES COUPLED WITH ACCUMULATING LAKE EFFECT
SNOW...EXPECT SIGNIFICANT TO SEVERE BLOWING/DRIFTING SNOW IN AND
NEAR THE LAKE EFFECT SNOW BANDS. ANY LOCATION THAT RECEIVES OVER 2
INCHES OF SNOW CAN EXPECT SIGNIFICANT BLOWING AND DRIFTING. EXPECT
THE WORST CONDITIONS TO BE FROM THE BUFFALO SOUTHTOWNS INTO SOUTHERN
ERIE...WYOMING...AND GENESEE COUNTIES. ALSO EAST OF LAKE ONTARIO
ACROSS MUCH OF JEFFERSON AND THE NORTHERN HALF OF LEWIS COUNTIES.
NOTE...THE WINTER STORM WATCHES ARE BEING REPLACED BY LAKE EFFECT
SNOW WARNINGS TO EMPHASIZE THE LOCALIZED NATURE OF THE HEAVIEST
SNOW. BLOWING/DRIFTING WILL BE HIT HARD IN THE STATEMENTS. ALSO...
THE WINTER STORM WATCH IS BEING CANCELLED OUTRIGHT FOR ALLEGANY
COUNTY. MODELS CONTINUE TO TREND FARTHER NORTH WITH THE LAKE
SNOWS...AND EXPECT ALLEGANY COUNTY TO MISS MOST IF NOT ALL OF THIS
EVENT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
BY THURSDAY EVENING THE CENTER OF THE INTENSE LOW PRESSURE SYSTEM
THAT CAUSED HAVOC ACROSS MUCH OF THE COUNTRY WILL BE NORTH OF
THE CANADIAN MARITIMES ALREADY BUT ITS EFFECTS WILL STILL BE FELT
ACROSS THE LOWER LAKES REGION INCLUDING OUR CWA THROUGH THE NIGHT
AND BEYOND. 850 MB TEMPERATURES WILL BE DROPPING TO MINUS 16 TO
MINUS 18C WITH LAKE INDUCED CAPES RISING TO OVER 700 JOULES PER
KILOGRAM AND EQUILIBRIUM LEVELS OVER 10 THOUSAND FEET. LAKE EFFECT
PLUMES WILL BE GOING STRONG EAST OF BOTH LAKES. THE BEST 925 MB
OMEGA FIELDS OFF LAKE ERIE INDICATE A SOUTHWARD DRIFT OVERNIGHT WITH
THE TRADITIONAL SNOW BELT AREAS OF SOUTHERN ERIE AND WYOMING COUNTY
PROBABLY GETTING THE HEAVIEST SNOW ALONG WITH THE NORTHERN SECTIONS
OF CHAUTAUQUA AND CATTARAUGUS COUNTIES. ACCUMULATION RATES OF SNOW
MAY BE AS HIGH AS 2 INCHES PER HOUR. STRONG WINDS WILL CONTINUE TO
PRODUCE TREACHEROUS DRIVING CONDITIONS IN BADLY BLOWN SNOW. OFF LAKE
ONTARIO THE LATEST PROJECTED 925 MB OMEGA FIELDS REALLY HAMMER THE
TUG HILL PLATEAU WITH ONLY A MINOR SHIFT TO THE SOUTH.
MORE OF THE SAME ON FRIDAY AS LAKE EFFECT PARAMETERS REMAIN HEALTHY.
WINDS WILL STILL BE NOTICEABLE BUT NOT AS STRONG. NAM12 MODEL
STEERING WINDS INDICATE THE LAKE ERIE BAND WILL OSCILLATE NORTH
AGAIN FOR AWHILE...MAYBE AS FAR NORTH AS BUFFALO BEFORE SHIFTING
SOUTH AGAIN FRIDAY NIGHT. THE PLUME OFF LAKE ONTARIO LOOKS LIKE IT
WILL STAY FAIRLY STEADY STATE ALTHOUGH SMALL OSCULATIONS CAN BE
EXPECTED.
BY SATURDAY MORNING THE STEERING WINDS FAVOR A 280 FLOW OFF BOTH
LAKES WITH A SOUTHWARD SHIFT CONTINUING DURING THE DAY. THE LAKE
EFFECT WILL LIKELY BECOME MORE DIFFUSE SATURDAY AFTERNOON AND NIGHT
AS SURFACE HIGH PRESSURE MOVING IN FROM THE WEST LOWERS THE
EQUILIBRIUM LEVEL.
WHEN ALL IS SAID AND DONE THE HARDEST HIT AREAS EAST OF LAKE ERIE
WILL LIKELY END UP WITH 2 TO 3 FEET OF SNOW AND THE TUG HILL AREA
WILL LIKELY GET MORE THAN 3 FEET.
EXPECT A COLD NIGHT SATURDAY NIGHT AS WINDS LIGHTEN. A FRESH
SNOWPACK...ESPECIALLY DOWNWIND OF THE LAKES...WILL GUARANTEE BELOW
NORMAL TEMPERATURES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
SUNDAY SFC HIGH PRESSURE WILL SLOWLY SLIDE OFF THE NEW ENGLAND
COASTLINE. ALL LAKE EFFECT SNOW SHOULD HAVE ENDED BY SUNDAY WITH
SKIES A MIX OF CLOUDS AND SUN. WENT WITH THE 12Z ECMWF AND 12Z GGEM
WHICH KEEPS THE REGION DRY SUNDAY...WHICH IS ALSO CONTINUITY. THE
12Z GFS DEVELOPS A WEAK SHORTWAVE ACROSS THE REGION WITH
PRECIPITATION BUT WITH LITTLE ENSEMBLE SUPPORT FROM THE MREF...WILL
MAINTAIN A DRY DAY.
UNCERTAINTY IN THE FORECAST INCREASES TO START THE WORK WEEK. THE
ECMWF DELAYS A COLD FRONT TILL MUCH LATER IN THE WEEK...WHILE THE
12Z GFS BRINGS A COLD FRONT ACROSS THE REGION TUESDAY NIGHT. THE
GGEM PLACES A COLD FRONT ON OUR DOORSTEPS TUESDAY MORNING.
FOR NOW WILL CARRY LOW CHANCE POPS MONDAY NIGHT THROUGH WEDNESDAY.
WITH TEMPERATURES NEAR NORMAL...AND POTENTIALLY ABOVE NORMAL
DEPENDING ON TIMING OF COLD FRONT. THESE TEMPERATURES WILL ALLOW FOR
SOME RAIN/MIXED PRECIPITATION AHEAD OF THE NEXT COLD FRONT.
BOTH MODELS DO AGREE THAT THERE WILL BE A VERY COLD AIRMASS BEHIND
THIS FRONT OVER THE UPPER LAKES BY MIDWEEK WITH 850 MB TEMPS OF -25C
OR LOWER. SOME OF THIS MAY BE DRAWN DOWN INTO OUR REGION BY LATER
NEXT WEEK...SO LOOK FOR BELOW NORMAL TEMPS.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
INTENSE LOW PRESSURE CENTERED OVER LAKE MICHIGAN WILL MOVE TO THE
NORTHEAST AND REACH GEORGIAN BAY BY LATE AFTERNOON...THEN CONTINUE
ON INTO WESTERN QUEBEC TONIGHT. A COLD FRONT TRAILING SOUTH OF THE
LOW WILL CROSS WESTERN NEW YORK LATE THIS AFTERNOON...THEN TRACK
ACROSS THE REST OF THE AREA THIS EARLY THIS EVENING. A BAND OF
SHOWERS AND POSSIBLE THUNDERSTORMS WILL ACCOMPANY THE FRONT
PASSAGE.
BEHIND THE FRONT...A STRONG SOUTHWESTERLY FLOW OF MUCH COLDER AIR
WILL OVERSPREAD THE REGION THIS EVENING...WITH SUSTAINED SURFACE
WINDS INCREASING INTO THE 25-35 KNOT RANGE...WITH GUSTS REACHING AS
HIGH AS 45-50 KNOTS. AS THE COLDER AIR OVERSPREADS THE RELATIVELY
WARMER GREAT LAKES...SNOW SQUALLS WILL ALSO DEVELOP NORTHEAST OF THE
LAKES...AFFECTING THE KBUF/KIAG TERMINALS THIS EVENING...AND KART
BEGINNING OVERNIGHT. THE COMBINATION OF THE SNOW SQUALLS AND STRONG
WINDS WILL RESULT IN CONDITIONS DETERIORATING TO IFR AND THEN LIFR
IN THE AREAS OF LAKE EFFECT TONIGHT...WITH SOME IFR TO MVFR SNOW
SHOWERS FOUND ELSEWHERE.
VERY WINDY CONDITIONS AND AREAS OF LAKE EFFECT SNOW WILL PREVAIL
THROUGH THURSDAY. THE STEADIEST LAKE SNOWS OFF LAKE ERIE ARE
EXPECTED TO SET UP JUST SOUTH OF KBUF...WHILE THE HEAVIER SNOW EAST
OF LAKE ONTARIO WILL IMPACT KART. IFR TO LIFR CONDITIONS WILL BE
COMMON WITHIN THE MAIN SNOWBANDS. OTHERWISE...EXPECT MVFR TO VFR
CONDITIONS IN SCATTERED SNOW SHOWERS AND BLOWING SNOW.
OUTLOOK...
THURSDAY NIGHT...MAINLY MVFR/IFR SNOW SHOWERS AND SQUALLS...MAINLY
SOUTH OF KBUF. STRONG SURFACE WINDS CONTINUING.
FRIDAY...VFR/MVFR IN SNOW SHOWERS.
SATURDAY...VFR/MVFR IN SNOW SHOWERS.
SUNDAY AND MONDAY...MAINLY VFR.
&&
.MARINE...
A VERY DEEP STORM SYSTEM WILL CONTINUE ON ITS TREK NORTHEASTWARD
TONIGHT...REACHING AN AREA NORTH OF THE CANADIAN MARITIMES BY
THURSDAY EVENING. THE STRONG PRESSURE GRADIENT ASSOCIATED WITH THIS
SYSTEM WILL CONTINUE TO PRODUCE STRONG WINDS ACROSS THE LOWER LAKES
REGION.
FOR LAKE ONTARIO...WINDS WILL INCREASE TO GALE FORCE TONIGHT WITH
OCCASIONAL STORM FORCE WIND GUSTS LATE TONIGHT INTO THURSDAY
MORNING.
AS THE DEEP LOW LIFTS AWAY ACROSS QUEBEC THURSDAY NIGHT AND
FRIDAY...WINDS WILL VERY SLOWLY SUBSIDE ACROSS BOTH LAKES.
WAVES ON BOTH LAKES WILL LIKELY BUILD TO BETWEEN 15 AND 20 FEET.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...HIGH WIND WARNING UNTIL 7 PM EST THURSDAY FOR NYZ001-002-007-
008-010>012-019>021-085.
LAKESHORE FLOOD WARNING UNTIL 7 AM EST THURSDAY FOR NYZ010-019-
085.
LAKE EFFECT SNOW WARNING FROM 2 AM THURSDAY TO 7 AM EST
SATURDAY FOR NYZ012-085.
LAKE EFFECT SNOW WARNING FROM 2 AM THURSDAY TO 1 PM EST
SATURDAY FOR NYZ007-008.
HIGH WIND WARNING UNTIL 7 PM EST THURSDAY FOR NYZ003>006-013-
014.
LAKE EFFECT SNOW WARNING FROM 1 PM THURSDAY TO 1 PM EST
SATURDAY FOR NYZ006.
LAKE EFFECT SNOW ADVISORY FROM 1 AM TO 7 PM EST THURSDAY FOR
NYZ003.
LAKE EFFECT SNOW ADVISORY FROM 10 PM THIS EVENING TO 9 AM EST
THURSDAY FOR NYZ001-002.
LAKE EFFECT SNOW WARNING FROM 4 AM THURSDAY TO 7 AM EST
SATURDAY FOR NYZ019-020.
LAKE EFFECT SNOW WARNING FROM 10 PM THIS EVENING TO 10 PM EST
THURSDAY FOR NYZ010-011.
LAKE EFFECT SNOW ADVISORY FROM 7 AM THURSDAY TO 7 AM EST
FRIDAY FOR NYZ013-014.
MARINE...STORM WARNING UNTIL 7 PM EST THURSDAY FOR LEZ020-040-041.
GALE WARNING FROM 7 PM THIS EVENING TO 7 PM EST
THURSDAY FOR LOZ042>045-062>065.
GALE WARNING FROM 1 AM TO 7 PM EST THURSDAY FOR
SLZ022-024.
&&
$$
SYNOPSIS...SAGE
NEAR TERM...HITCHCOCK
SHORT TERM...SAGE
LONG TERM...THOMAS
AVIATION...TJP
MARINE...SAGE
