FXUS61 KBUF 050307
AFDBUF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1007 PM EST FRI DEC 4 2009
.SYNOPSIS...
ANY LINGERING LAKE EFFECT SNOW WILL DIMINISH TONIGHT AS HIGH
PRESSURE RIDGES NORTH FROM THE OHIO VALLEY. THE HIGH WILL KEEP
MAINLY DRY CONDITIONS ACROSS THE AREA THIS WEEKEND BEFORE AN
APPROACHING LOW BRINGS A CHANCE FOR SNOW MONDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 930 PM...AREA RADARS SHOW LK EFFECT HAVING A TOUGH TIME
GETTING GOING. NAM BUFKIT PROFILE FOR BUF SHOWED MAIN THREAT FOR
RE-GENERATION TO OCCUR TO BE BEFORE MIDNIGHT WITH STRONGEST OMEGA,
BEST LOW LVL MOISTURE AND CRYSTAL GROWTH FROM ARND 02Z-04Z. SO CAN'T
SEE GOING ANYTHING HIGHER THAT CHC POPS FOR TONIGHT MAINLY FROM
BETWEEN BUFFALO AND AREAS NORTH OF JAMESTOWN. AMNTS A COATING TO
LESS THAN AN INCH AT MOST IN SOME SPOTS.
EAST OF LAKE ONTARIO, WILL MAKE SIMILAR CHANGES WITH SW FLOW KEEPING
CHC POPS MAINLY ACROSS JEFFERSON COUNTY AND NORTHERN HALF OF LEWIS
COUNTY. AMNTS THERE GENLY A COATING TO AN INCH POSSIBLE IN SPOTS.
EARLIER DISCO BELOW FOR LK ONTARIO,
AS WE LOSE DIURNAL INFLUENCES...EXPECT THAT THIS ACTIVITY SHOULD
TEND TO REDEVELOP ACROSS JEFFERSON/LEWIS COUNTIES ON A WSW FLOW THIS
EVENING...BEFORE DIMINISHING OVERNIGHT AS THE LOW LEVEL FLOW WEAKENS
AND BECOMES INCREASINGLY SHEARED...WITH THE ACTIVITY EVENTUALLY
FALLING APART BY SATURDAY MORNING. AS IS THE CASE OFF OF LAKE
ERIE...THE 6-7 KFT CAP AND VERY LIMITED SNOW GROWTH REGION SHOULD
ALSO KEEP THE LAKE ONTARIO LAKE EFFECT FROM PRODUCING MORE THAN AN
INCH IN THE WAY OF ACCUMULATION.
IN BETWEEN...THE GENESEE VALLEY AND FINGER LAKES REGIONS SHOULD SEE
A GENERALLY DRY AND QUIET NIGHT TONIGHT...WITH JUST AN INCREASE IN
MID AND UPPER LEVEL CLOUD COVER LATER TONIGHT IN ADVANCE OF LOW
PRESSURE THAT WILL BE LIFTING NORTHEAST OFFSHORE OF THE SOUTHEASTERN
US COAST.
ON SATURDAY...LOW-LEVEL RIDGING WILL REMAIN INTACT ACROSS OUR
AREA...WHILE THE AFOREMENTIONED LOW CONTINUES TO LIFT NORTHEAST
OFFSHORE OF THE EAST COAST. THIS WILL RESULT IN A DRY AND QUIET DAY
ACROSS OUR AREA ALONG WITH SEASONABLE TEMPERATURES...WHILE THE
PRECIP FROM THE COASTAL SYSTEM REMAINS TO OUR SOUTH AND EAST. ABOUT
ALL WE WILL SEE FROM THIS SYSTEM WILL BE SOME MID AND HIGH CLOUD
COVER...WHICH SHOULD RESULT IN MORE CLOUDS THAN SUN ACROSS OUR AREA.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
RATHER TRANQUIL WEATHER IS EXPECTED SATURDAY NIGHT AND SUNDAY WITH
HIGH PRESSURE FORECAST TO SLIDE EAST ACROSS THE MIDDLE ATLANTIC
STATES. A COLD NORTHWEST FLOW IN THE WAKE OF A DEPARTING COASTAL LOW
MAY GENERATE SOME LIMITED LAKE EFFECT SNOW SHOWERS SOUTHEAST OF THE
LAKES SATURDAY NIGHT...WITH SOME SNOW POSSIBLY LINGERING SOUTHEAST
OF LAKE ONTARIO INTO SUNDAY MORNING.
LOW PRESSURE HEADING EAST FROM THE CENTRAL GREAT LAKES WILL BRING A
CHANCE OF LIGHT SNOW MONDAY. COLDER AIR ADVECTING BEHIND THIS LOW
WILL GENERATE SOME LAKE EFFECT SNOW SOUTHEAST OF THE LAKES
MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE RIDGING ACROSS SOUTHERN QUEBEC AND NEW YORK STATE WILL
BRING DRY CONDITIONS TUESDAY AFTER ANY SNOW SHOWERS LINGERING
SOUTHEAST OF LAKE ONTARIO DISSIPATE.
THE MAIN FOCUS WILL THEN SHIFT TO AN AREA OF LOW PRESSURE THAT IS
FORECAST TO LIFT OUT OF THE FOUR CORNERS AREA AND REACH THE CENTRAL
GREAT LAKES WEDNESDAY. MOISTURE SURGING AHEAD OF THIS SYSTEM WILL
SPREAD A GENERAL SNOW ACROSS THE AREA TUESDAY NIGHT INTO MORNING
MORNING. THE LATEST GUIDANCE STILL SUGGESTS THAT BOUNDARY LAYER
TEMPERATURES WILL WARM UP ENOUGH BY WEDNESDAY AFTERNOON TO CAUSE A
CHANGEOVER TO ALL RAIN OVER THE LOWER ELEVATIONS...WITH A RAIN/SNOW
MIX LIKELY ACROSS THE HIGHER ELEVATIONS.
GIVEN THE TRACK OF THIS LOW AND ITS DEEPENING CHARACTER...STRONG
WINDS WILL DEVELOP AHEAD OF THE LOW ON WEDNESDAY...DIMINISH SOME AS
THE LOW PASSES WED EVENING...THEN INCREASE AGAIN WED NIGHT AND
CONTINUE STRONG THROUGH THURSDAY. THE MODEL WINDS SHOW GALES ON THE
LAKES AND THE POTENTIAL FOR WIND ADVISORY ON THE LAND. ALSO...THE
COLD AIR TRAILING THE LOW WILL BE SUFFICIENTLY COLD FOR LAKE EFFECT
ON THURSDAY WITH 850MB TEMPS FALLING TO THE MINUS TEENS THURSDAY
NIGHT.
THE MAIN CENTER OF THE LOW IS FORECAST TO MOVE TOWARD LABRADOR
FRIDAY WHILE HIGH PRESSURE BUILDS INTO THE MIDDLE ATLANTIC STATES.
THE COLD NORTHWEST FLOW BETWEEN THESE TWO SYSTEMS STILL GENERATE
SOME LAKE EFFECT SNOW INTO FRIDAY.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
DURING THE FORECAST PERIOD...LOW-LEVEL RIDGING WILL BE OVER THE
REGION...WHILE LOW PRESSURE DEVELOPS NEAR FLORIDA AND LIFTS
NORTHEAST PARALLEL TO THE EAST COAST...REACHING A POSITION OFF OF
THE JERSEY COAST BY SATURDAY EVENING.
VFR CONDITIONS WILL PREVAIL ACROSS MUCH OF THE REGION THROUGH THE
TAF PERIOD. THE EXCEPTION WILL BE NORTHEAST OF THE LAKES. THE NAM
BUFKIT PROFILE FOR KBUF SHOWS THE POTENTIAL FOR SOME LK EFFECT SNOW
TO DEVELOP THIS EVENING FROM AROUND 01Z TO 05Z NE OF LK ERIE AS LOW
LVL MOISTURE INCREASES BELOW 5 THSD FT AS WELL AS OMEGA WITH CRYSTAL
GROWTH DEVELOPING AT THE TOP OF THIS MOIST LYR UNTIL ARND MIDNIGHT.
HAVE PUT IN A PERIOD OF MVFR WITH OCNL IFR CONDITIONS AT KBUF DURG
THIS PERIOD. OTHERWISE EXPECT THIS ACTIVITY TO WEAKEN OVERNIGHT AS
THE LOW LVL WINDS BECOME INCREASINGLY SHEARED OVERNIGHT.
NE OF LK ONTARIO, DO NOT EXPECT MUCH IN THE WAY OF ANY LK EFFECT
ACTIVITY TIL VERY LT TONIGHT AROUND THE KART TAF SITE AS ICE CRYSTAL
GROWTH REGION IS LACKING IN THE KART BUFKIT PROFILE. SOME MESOSCALE
MODELS DO DEVELOP SOME LK ARND KART AFTER ARND 07Z SO AT THIS TIME
WILL PUT IN SOME OCNL MVFR CONDITIONS THROUGH 11Z AND THEN A PERIOD
OF MVFR CONDITIONS FRM ARND 11Z-15Z.
OUTLOOK...
SATURDAY NIGHT...VFR. LOW CHC OF SOME LK EFFECT SE OF LKS.
SUNDAY...VFR WITH A CHANCE OF SNOW SHOWERS SOUTHEAST OF LK ONTARIO.
MONDAY...VFR/MVFR WITH A CHANCE OF SNOW.
TUESDAY...VFR.
WEDNESDAY...MVFR WITH RAIN/SNOW.
&&
.MARINE...
HAVE DROPPED SMALL CRAFT ADVSRYS FOR NEARSHORES OF LK ERIE AND LK
ONTARIO FROM THE NIAGARA RIVER TO SODUS BAY AS WINDS AND WAVES HAVE
DROPPED BELOW SMALL CRAFT ADVSRY CRITERIA. ALSO DROPPED SMALL CRAFT
ADVSRY FOR THE UPPER NIAGARA RIVER AND BUFFALO HARBOR.
WILL CONTINUE THEM THROUGH 09Z ON THE EAST END OF LK ONTARIO AS
WESTERLY WINDS WILL KEEP WAVES IN 3-5 FT RANGE TIL LTR TONIGHT.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST SATURDAY FOR LOZ044-045.
&&
$$
SYNOPSIS...TJP
NEAR TERM...JJP/JJR
SHORT TERM...TJP
LONG TERM...TJP/WCH
AVIATION...JJP/JJR/TJP
MARINE...JJP
