FXUS61 KBUF 291207
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
707 AM EST SUN NOV 29 2009

.SYNOPSIS...
A SOUTHERLY FLOW OF MILDER AIR WILL OVERSPREAD THE REGION TODAY 
BETWEEN HIGH PRESSURE MOVING OFF THE CAROLINA COAST AND LOW PRESSURE 
MOVING EAST FROM THE CENTRAL LAKES. AS THE LOW CROSSES THE AREA IT 
WILL SPREAD SHOWERS ACROSS THE REGION TONIGHT. A NORTHWEST FLOW OF 
COLDER AIR WILL FOLLOW THE SYSTEM LATER TONIGHT AND MONDAY. A 
SECONDARY TROUGH IS EXPECTED TO CROSS THE AREA TUESDAY MORNING.

&&

.NEAR TERM /THROUGH TONIGHT/...
SENT OUT AN UPDATE TO COVER THE GROWING AREA OF STRATUS FROM NEAR
NIAGARA FALLS TO ROCHESTER AND WATERTOWN. THIS SHOULD ERODE AGAIN
THIS MORNING. OTHER THAN THAT IT LOOKS LIKE A GREAT END TO THE
WEEKEND. IT WILL NOT SEEM AT ALL LIKE LATE NOVEMBER.

AS OF 08Z A SURFACE HIGH WAS CRESTING OVER CENTRAL NEW YORK. IT IS 
EXPECTED TO MOVE OFF THE NEW ENGLAND COAST THIS AFTERNOON WITH A 
SOUTHERLY LOW LEVEL FLOW OVER OUR REGION AHEAD OF LOW PRESSURE 
DEEPENING OVER THE CENTRAL GREAT LAKES. WE SHOULD GET PLENTY OF 
SUNSHINE EARLY THEN INCREASING CLOUDS FROM NORTHWEST TO SOUTHEAST AS 
THE DAY WEARS ON AND THE LOW MOVES EAST. THE SUNSHINE AND DOWNSLOPE 
FLOW SHOULD ALLOW TEMPERATURES TO PEAK SOMEWHERE IN THE LOWER 50S IN 
THE LAKE PLAIN AND AT LEAST APPROACHING 50 OVER THE NORMALLY COLDER 
HIGHER ELEVATIONS OF THE SOUTHERN TIER AND THE EASTERN LAKE ONTARIO 
COUNTIES. THIS IS A GOOD 10 DEGREES ABOVE NORMAL.

WE HAVE BACKED OFF A LITTLE MORE ON THE PRECIPITATION TIMING WITH 
THE APPROACHING LOW AND ASSOCIATED COLD FRONT. WE WILL GO CLOSER TO 
THE LATEST NAM SOLUTION WHICH IS A LITTLE SLOWER THAN THE GFS.

BIG CHANGES BEGIN TONIGHT. THE ABOVE MENTIONED LOW IS EXPECTED TO 
MOVE TO NORTHERN NEW YORK BY MORNING WHILE CONTINUING TO DEEPEN. IT 
WILL DRAG ITS ASSOCIATED COLD FRONT THROUGH THE ENTIRE CWA BY 12Z. 
WE WILL HOLD ONTO THE CATEGORICAL POPS CONSIDERING FRONTAL LIFT AND 
FAVORABLE JET DYNAMICS. WE WILL BE IN THE LEFT FRONT QUADRANT OF THE 
250 MB JET AND ALSO AT THE NOSE OF THE 850 MB JET. PRECIP TYPE WILL 
LIKELY REMAIN RAIN ALTHOUGH A MIX IS POSSIBLE BY DAYBREAK WEST AND 
NORTH.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
ON MONDAY, THE COLD FRONT IS EXPECTED TO BE IN THE VCNTY OF CENTRAL 
NEW YORK IN THE MORNING AS THE LOW SFC LOW MOVES EAST FROM NORTHERN 
VT IN THE MRNG TO MAINE BY EARLY AFTERNOON. THE TRAILING MID 
LEVEL TROUGH/SHORT WAVE WILL MOVE THROUGH THE AREA DURING THE 
MORNING AND MOVE EAST OF THE AREA AFTER 18Z. SFC RIDGING FOLLOWS 
DURING THE AFTERNOON. EXPECT MORNING HIGHS GENERALLY FROM THE UPPER 
30S TO AROUND 40 WITH TEMPERATURES STEADY OR FALLING SLOWLY DURING 
THE AFTERNOON. 

WILL GO WITH LKLY POPS IN THE MORNING EAST OF LK ONTARIO DUE TO THE 
VCNTY OF THE COLD FRONT WITH LKLY POPS HANGING BACK ACROSS THE 
SOUTHERN FINGER LKS AND THE HIGHER TERRAIN SOUTH AND SOUTHEAST OF 
BUFFALO, ACROSS THE SOUTHERN TIER. WILL LOWER POPS TO CHC RANGE IN 
THE AFTERNOON ACROSS THE SOUTHERN TIER AND AREAS FROM BUFFALO AND 
ROCHESTER SOUTH DUE TO THE COLD WNW UPSLOPE FLOW. WILL CONTINUE LKLY 
POPS THROUGH THE AFTERNOON ACROSS UPSLOPE AREAS EAST OF LK ONTARIO. 
PRECIP TYPE SHLD BE RAIN SHWRS EARLY BUT A MIX DEVELOPING DURGING 
THE DAY ESPCLY ACROSS HIGHER TERRAIN WHERE IT SHLD EVENTUALLY CHANGE 
TO ALL SNOW.   

TEMPERATURES FALL TO THE MID 20S TO LOWER 30S MONDAY NIGHT. A SFC 
TROUGH MOVING EAST FROM THE CENTRAL LKS WILL BRING CHC SNOW SNOWERS 
WITH LAKE SNOWS EXPECTED TO THE EAST OF THE LAKES...POPS IN THE CAT 
RANGE ALONG THE CHAUTAUQUA RIDGE WITH ACCUMS GENLY IN THE 2-4 INCH 
RANGE WITH A COUPLE OF INCHES POSSIBLE EAST OF LK ONTARIO.

TUESDAY, THE SFC TROUGH MOVES EAST ACROSS THE AREA IN THE MORNING. 
WINDS WILL BE SW ENOUGH AHEAD OF THE TROUGH IN THE MRNG TO BRING 
SOME LK ENHANCED SNOW TO THE BUF METRO AREA TUESDAY MRNG AND THEN IN 
THE AFTERNOON WINDS SHLD SHIFT NW AGAIN BEHIND THE TROUGH AND PUSH 
MOST OF THE PRECIP SOUTH AGAIN. SNOW SHWRS WILL ALSO BE LKLY EAST OF 
LK ONTARIO IN THE MORNING WITH A MIX IN THE AFTERNOON OVER LOWER 
ELEVATIONS. WILL CONTINUE CHC POPS TUESDAY EVENING ACROSS PORTIONS 
OF THE NORTH COUNTY WITH LINGERING LK EFFECT THERE. ELSEWHERE UPPER 
RIDGING...SOUTHWESTERLY WINDS AND WARMING WILL BRING AN END TO THE 
LAKE EFFECT AND BRING PARTIAL CLEARING TUESDAY NIGHT. IT WILL STILL 
BE QUITE COLD WITH OVERNIGHT LOWS IN THE MID 20S OVER MOST OF THE 
FORECAST AREA WITH SOME LOWER 30S ALONG THE LAKE ERIE SHORELINE 
AREAS.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGH PRESSURE PASSES THE REGION TO THE SOUTH WITH A NORTHWARD 
EXTENSION OF THE RIDGE COVERING THE EASTERN LAKES AND NORTHEASTERN 
STATES. SKIES WILL NOT CLEAR COMPLETELY DUE TO THE MOISTURE 
ADVECTING IN FROM THE SOUTH...BUT WE CAN EXPECT SOME SUNSHINE AND 
TEMPS IN THE MID 40S...A COUPLE OF DEGREES ABOVE SEASONAL NORMALS.

A PLAINS CLOSED UPPER LOW WILL OPEN AND LIFT ALONG THE WESTERN 
APPALACHIANS DURING WEDNESDAY AFTERNOON AND SPREAD PRECIP INTO THE 
FORECAST AREA DURING WEDNESDAY NIGHT. THIS TRACK IS ABOUT 200 MILES 
FARTHER INLAND ON TODAY'S 12Z GFS THAN ON PREVIOUS MODEL RUNS...AND 
WILL BRING A MIX OF RAIN AND SNOW TO THE AREA DURING THE NIGHT AS A 
WARM JET BOOSTS THE 850MB TEMPS CLOSE TO THE FREEZING MARK OVER THE 
GENESEE VALLEY AND FINGER LAKES BETWEEN 09Z AND 15Z...THEN BACK 
BELOW FREEZING FOR MUCH OF THE DAYTIME ON THURSDAY. WILL HAVE SOME 
MIXED PRECIP IN THE LATE NIGHT AND EARLY MORNING...THEN A MIX OF 
SNOW SHOWERS AND SOME SLEET AS THE SHALLOW WEDGE OF WARMER AIR IS 
UNDERLAIN BY COLDER AIR. THIS COMBINATION OF PRECIP TYPE MAY CHANGE 
IF THE NEWER MODELS SHIFT THE TRACK OF THE SURFACE LOW EITHER CLOSER 
TO THE COAST WHICH WILL MAINTAIN COLDER AIR AND ALL SNOW...OR 
FARTHER WEST WHICH WOULD BRING RAIN RATHER THAN SNOW. 

AS THE SURFACE LOW LIFTS NORTHWARD INTO WESTERN QUEBEC ON THURSDAY 
EVENING...THE FLOW ON THE WESTERN SIDE OF THE LOW WILL DRAW MUCH 
COLDER AIR INTO NEW YORK STATE DURING THURSDAY NIGHT...DEEPENING AND 
GETTING COLDER ON FRIDAY. THIS COULD SPELL THE BEGINNING OF A WELL 
DEVELOPED LAKE EFFECT SNOW EVENT WITH 850MB TEMPS FALLING TO A RANGE 
FROM -10C TO -12C BY LATE FRIDAY MORNING. WILL HAVE UPPER CHANCE TO 
LOW LIKELY POPS IN THE LEE OF THE LAKES FOR FRIDAY AND CHANCE POPS 
THROUGH SATURDAY MORNING.

WEDNESDAY WILL BE THE MILDEST DAY OF THE WORKWEEK WITH HIGHS IN THE 
LOWE TO MID 40S...THEN COLDER TEMPS THROUGH THE REST OF THE WEEK 
WITH LOWS IN THE MID TO UPPER 20S AND HIGHS ONLY IN THE MID TO UPPER 
30S.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
MOST OF THE AREA HAD CLEARED OUT OVERNIGHT BUT THE LATEST 11-3.9
MICRON SATELLITE SHOWS STRATUS REFORMING FROM NEAR KIAG ACROSS
LAKE ONTARIO AND KROC INTO THE KART REGION. WE WILL HAVE TO COVER
SOME BRIEF MVFR CIGS IN THOSE AREAS BUT GOOD VFR FLYING WILL BE
THE RULE DURING THE DAY.

CLOUDS WILL THICKEN UP THIS EVENING WITH AN APPROACHING GREAT
LAKES COLD FRONT. CONDITIONS WILL DROP TO MVFR WITH RAIN SHOWERS A
GOOD SHARE OF THE NIGHT.

OUTLOOK...
MONDAY...MVFR. CHANCE RAIN/SNOW SHOWERS. 
MONDAY NIGHT...MVFR WITH SCATTERED SHOW SHOWERS. LOCAL IFR/LIFR IN 
LAKE EFFECT SNOW EAST OF LAKES ERIE AND ONTARIO.
TUESDAY...VFR/MVFR. CHANCE RAIN/SNOW SHOWERS.
WEDNESDAY...MAINLY VFR.
THURSDAY...MVFR. CHANCE OF RAIN AND SNOW.

&&

.MARINE...
NO MARINE HEADLINES AT THIS TIME AS WINDS AND WAVES WILL BE BELOW 
SMALL CRAFT ADVSRY RANGE BUT THEY WILL BE NEEDED LATER TONIGHT INTO 
MONDAY ON LAKE ERIE AS SW WINDS INCREASE AHEAD OF THE COLD FRONT AND 
THEN SHIFT TO THE NW BEHIND THE FRONT LATER TONIGHT AND TUESDAY. 
ON LK ONTARIO SMALL CRAFT AVSRYS WILL LKLY BE NEEDED AS NW WINDS 
INCREASE BEHIND THE FRONT ON MONDAY AND CONTINUE MONDAY NIGHT.

&&

.CLIMATE...
STILL NO MEASURABLE SNOW SO FAR THIS SEASON OVER MOST OF WESTERN NEW 
YORK. WE ARE ALREADY OVER THREE WEEKS LATE (NORMAL DATES ARE NOV 7 
FOR BUFFALO AND NOV 8 FOR ROCHESTER). WE WILL AT LEAST GET TO MONDAY 
(30TH) AND IF SO...WILL BE THE LATEST IN 63 YEARS (1946) AT 
BUFFALO...AND LATEST IN 46 YEARS (1963) AT ROCHESTER. THE ALL TIME 
RECORD LATEST DATES FOR FIRST MEASURABLE SNOW ARE DEC 3 1899 AT 
BUFFALO AND DEC 10 1948 AT ROCHESTER.

IN ADDITION, ITS BEEN A LONG TIME SINCE EITHER BUFFALO OR ROCHESTER 
LAST SAW MEASURABLE SNOW. THROUGH TODAY NOV 29...BUFFALO WILL HAVE GONE
236 DAYS WITHOUT MEASURABLE SNOW, OR SINCE APRIL 7, 2009. THIS IS
THE 4TH LONGEST STRETCH IN 125 YEARS OF RECORDS. THE RECORD IS 277
DAYS SET BACK IN 1946. ROCHESTER IS ALSO AT 236 DAYS WITHOUT
MEASURABLE SNOW, OR THE 3RD LONGEST STRETCH THERE. THE RECORD IS
260 DAYS SET BACK IN 1952.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...JJP
NEAR TERM...SAGE
SHORT TERM...JJP
LONG TERM...WCH
AVIATION...HITCHCOCK/SAGE
MARINE...JJP
CLIMATE...TMA/SAGE