FXUS61 KBGM 102047
AFDBGM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
347 PM EST THU DEC 10 2009
.SYNOPSIS...
STRONG SOUTHWEST WINDS WILL CONTINUE THROUGH TONIGHT OVER CENTRAL NEW
YORK AND NORTHEAST PENNSYLVANIA. THE WINDS WILL GRADUALLY
DIMINISH OVERNIGHT. LAKE EFFECT SNOW SHOWERS WILL OCCUR ACROSS
UPSTATE NEW YORK FROM THE FINGER LAKES INTO THE TUG HILL PLATEAU
BEGINNING LATE TONIGHT AND INTO THE WEEKEND. SIGNIFICANT SNOW
ACCUMULATIONS WILL BE POSSIBLE ACROSS THE TUG HILL PLATEAU AND
PARTS OF THE MOHAWK VALLEY INTO SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
WILL ISSUE A LAKE EFFECT SNOW WARNING FOR NORTHERN ONEIDA COUNTY
BEGINNING LATE TONIGHT AND CONTINUING UNTIL SATURDAY. KTYX 88D
SHOWS SIGNIFICANT LAKE EFFECT SNOW BANDING EAST OF LAKE ONTARIO
NORTH OF ONEIDA COUNTY. THE POSITIONING OF THIS BAND IS THE MAIN
FORECAST PROBLEM THROUGH TONIGHT. KBUF 88D SHOWS A MUCH MORE
SOUTHWEST TO NORTHEAST ORIENTATION OF THE LAKE ERIE BAND
SUGGESTING LOW-LEVEL SOUTHWEST FLOW PREDOMINATES FARTHER WEST AT
THIS TIME. KTYX VAD WIND PROFILE SHOWS THAT THE LOW-LEVEL FLOW
BETWEEN 260 AND 270 DEGREES. SO I DON/T SEE THIS BAND SHIFTING
SOUTH UNTIL LATER TONIGHT.
ALL THREE MESOSCALE MODELS AND THE LAKE EFFECT SUPERENSEMBLE
FORECAST SYSTEM ALL INDICATE AN EVENTUAL SOUTHWARD SHIFT OF THE
LAKE ONTARIO SNOW BANDS. THE UPPER LEVEL FLOW WILL EVENTUALLY
SHIFT TO A MORE WEST TO NORTHWEST DIRECTION LATER TONIGHT AND
CONTINUE THROUGH FRIDAY AND FRIDAY NIGHT.
THE LOCAL WRF MODEL SEEMS TO HAVE THE BEST HANDLE ON THE CURRENT
POSITION OF THE LAKE EFFECT SNOW BANDS AND HAVE FOLLOWED ITS
DEPICTION OF THE EVOLUTION OF THIS SNOW BAND CLOSELY IN THIS FORECAST.
HENCE WILL BRING SNOWBAND INTO NORTHERN ONEIDA COUNTY AFTER 05Z.
MODEL GUIDANCES SHOWS THAT THE BAND DOES NOT SINK INTO CENTRAL OR
SOUTHERN ONEIDA COUNTY UNTIL SATURDAY.
NEXT CONCERN IS INTENSITY OF THE SNOWS. BUFKIT MODEL SOUNDINGS
FROM THE NAM, GFS, LOCAL WRF ALL SHOW STRONG OMEGA WELL WITHIN THE
DENDRITIC SNOW GROWTH ZONE BEGINNING LATE TONIGHT AND CONTINUING
INTO FRIDAY. ADDITIONALLY, THE LOW-LEVEL MOISTURE WAS PLENTIFUL ON
THE BACKSIDE OF THE MAJOR CYCLONE THAT TRACKED TO OUR NORTH
YESTERDAY. ALL THIS COMBINED WITH UPSLOPE FLOW MEANS HEAVY SNOW.
FORECAST CONSENSUS HERE IS FOR AROUND 2 FEET IN THE FAR NORTH PART
OF ONEIDA COUNTY WITH AMOUNTS RAPIDLY TAPERING DOWN TO 3-4 INCHES
IN CENTRAL ONEIDA COUNTY. BELIEVE BAND STAYS NORTH OF KRME UNTIL
SATURDAY. THIS COULD CHANGE AND THIS WILL BE WATCHED LATER SHIFTS.
THE SNOW WILL BE HEAVY ENOUGH AND COMBINED WITH THE WIND WILL
CAUSE WHITEOUT CONDITIONS. NEEDLESS TO SAY, TRAVEL WILL BECOME
VERY DANGEROUS IN NORTHERN ONEIDA COUNTY LATE TONIGHT THROUGH
FRIDAY. THUS LAKE EFFECT SNOW WARNING IS JUSTIFIED.
AS FOR WIND ADVISORIES...GUIDANCE CONTINUES TO INDICATE ADVISORY
LEVEL WINDS, ESPECIALLY IN THE NORTHERN PART OF THE WFO BINGHAMTON
FORECAST AREA AND OVER THE HIGHER TERRAIN. WILL KEEP WIND ADVISORY
UNTIL 4 AM. MIDNIGHT SHIFT COULD EXTEND FURTHER IN TIME IF
NEEDED.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
NEXT CONCERN IS WHETHER LAKE ERIE SNOWBANDS REACH INTO THE CENTRAL
SOUTHERN TIER OF NY AND WESTERN FINGER LAKES. LOCAL WRF MODELS
SUGGESTS SOME OF THIS LAKE EFFECT SNOW GETS INTO THESE AREAS
BETWEEN 9 AND 12Z FRIDAY. QPF AMOUNTS ARE NOT THAT IMPRESSIVE AS
PER MODEL GUIDANCE. WILL HAVE LIKELY POPS FOR SNOW SHOWERS AND
HAVE 2-4 INCHES OF ACCUMULATION LATE TONIGHT INTO FRIDAY. THIS WILL BE
SOMETHING FOR LATER SHIFTS TO WATCH. THE INLAND PENETRATION OF THE
LAKE ERIE BAND IS ALWAYS TROUBLESOME TO FORECAST.
BY SATURDAY MORNING THE FLOW TURNS MORE NORTHWESTERLY AS STRONG SUBSIDENCE
WORKS IN AND LOWERS THE INVERSION. WILL HAVE LAKE EFFECT WARNING
EXPIRE AT 18Z SATURDAY. THE BAND WILL MIGRATE TO CENTRAL AND
SOUTHERN ONEIDA COUNTY SATURDAY BUT IT WILL BE FALLING APART SO I
DON/T ANTICIPATE ANY HEAVY ACCUMULATIONS SOUTH OF THE WARNING
AREA. AGAIN THIS WILL BE SOMETHING TO WATCH FOR ON LATER SHIFTS
BUT AS IT STANDS NOW, GUIDANCE DOES NOT SUGGEST A SOUTHWARD SHIFT
UNTIL THE LAKE EFFECT EPISODE IS NEARLY OVER. IN ADDITION, OUR
MESOSCALE MODELS HISTORICALLY HAVE HAD A SOUTHWARD BIAS TO THE
POSITIONING OF LAKE EFFECT BANDS. THERE HAS BEEN SOME CHANGES MADE TO
THE MODELS AND IT WILL BE INTERESTING TO SEE IF THIS BIAS WILL
CONTINUE THIS WINTER.
FOR SATURDAY NIGHT...HIGH PRESSURE BRIEFLY BUILDS IN BEFORE NEXT
SYSTEM ARRIVES FOR SUNDAY. THE GFS IS FASTER THAN THE NAM IN
BRINGING CLOUDS AND PRECIPITATION. THE 12Z EURO AND 12Z GEM SEEMS
TO BE CLOSER TO THE GFS. HENCE WILL GO WITH FASTER TIMING TO
PRECIPITATION FOR SUNDAY. PRECIPITATION-TYPE WILL BE TRICKY. IT
LOOKS LIKE A SNOW TO SLEET AND FREEZING RAIN MIXTURE. THE GEM
SUGGESTS ALL SNOW. FOR NOW WILL HAVE MIXED PRECIPITATION IN GRIDS
AND ZONES. QPF AMOUNTS ARE FAIRLY LIGHT SO THIS DOES NOT LOOK LIKE
A MAJOR STORM. THERE IS A POTENTIAL FOR SOME FREEZING RAIN SO
WILL MENTION IN HWO.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
MIXED PRECIPITATION WILL PROBABLY LINGER INTO SUNDAY
EVENING...BEFORE DIMINISHING LATE AT NIGHT...AS THE COASTAL WAVE
PUSHES FARTHER OFF SHORE AT THAT POINT.
IN GENERAL...MODEL CONSENSUS INDICATES THAT MONDAY AND TUESDAY
WILL BE SOMEWHAT MILDER THAN RECENT DAYS...AS A SOUTHERLY TO
SOUTHWESTERLY FLOW PATTERN SETS UP...IN ADVANCE OF A STRONG
MIDWESTERN COLD FRONT. FAIRLY ABUNDANT MOISTURE...AND THE PASSAGE
OF FAST MOVING UPPER-LEVEL WAVES...WILL BRING THE CHANCE OF RAIN
OR SNOW SHOWERS THIS PERIOD.
BY THE MIDDLE OF NEXT WEEK...A PROGRESSIVELY COLDER PATTERN SHOULD
RETURN...BEHIND THE ABOVE MENTIONED COLD FRONT. NORTHERLY TO
NORTHWESTERLY WINDS...MOVING ACROSS THE UPSTREAM GREAT
LAKES...SHOULD LEAD TO A CHANCE OF SNOW SHOWERS OR FLURRIES...
FOR WEDNESDAY THROUGH THURSDAY.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
LES SNOW CONTS OFF BOTH LAKES THIS AFTN. ONTARIO BAND REMAINS
NORTH OF THE FCST POINTS AND WITH THE WLY FLOW SHD CONT TO REMAIN
NORTH. SOMEWHAT MORE SHEARED ERIE BAND CONTS ACROSS THE NRN FINGER
LAKES...AND IS FCSTD BY THE LCL WRF TO DROP SLOWLY SOUTH ACROSS
THE CNTRL AND SRN FINGER LAKES. THIS SHD BRING SOME HEAVIER LES SHWRS
INTO ITH...ELM...AND BGM LATE TNGT AND INTO EARLY FRI WITH VSBY
AND CIGS OCNLY IN THE MVFR RANGE.
WINDS WILL REMAIN STRONG AND GUSTY OUT OF THE WEST AS THE LRG UPR
TROF REMAINS NEARLY STATIONARY OVER SE CANADA.
OUTLOOK...
FRIDAY THROUGH SATURDAY...HIGHLY VARIABLE CIGS/VSBYS AT KSYR-KRME
WITH LAKE EFFECT SNOW SHOWERS IN THE VICINITY. VFR WITH SCT-BKN
CIGS AND A CHC OF MVFR CIGS KITH-KELM-KBGM-KAVP.
SUNDAY...VFR.
MONDAY...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND ADVISORY UNTIL 4 AM EST FRIDAY FOR PAZ038>040-043-044-047-
048-072.
NY...WIND ADVISORY UNTIL 4 AM EST FRIDAY FOR NYZ009-015>018-022>025-
036-037-044>046-055>057-062.
LAKE EFFECT SNOW WARNING FROM MIDNIGHT TONIGHT TO 1 PM EST
SATURDAY FOR NYZ009.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...MLJ
AVIATION...DGM/10
