Area Forecast Discussion
Issued by NWS Buffalo, NY

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FXUS61 KBUF 251106
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
706 AM EDT SAT OCT 25 2014

.SYNOPSIS...
A COLD FRONT OVER LOWER MICHIGAN WILL SWEEP ACROSS OUR FORECAST AREA
THIS AFTERNOON AND EVENING...AND THIS WILL LEAD TO SOME GUSTY WINDS
ALONG WITH THE POTENTIAL FOR SOME SHOWERS. COOLER AIR IN THE WAKE OF
THE FRONT WILL THEN SET THE STAGE FOR SOME NUISANCE LAKE EFFECT RAIN
SHOWERS EAST OF LAKE ONTARIO TONIGHT AND SUNDAY...WHILE THE
REMAINDER OF WESTERN NEW YORK WILL BE COOLER WITH BRISK WINDS. A
SIGNIFICANT WARMING TREND CAN BE EXPECTED EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE NOSING NORTH FROM THE MID ATLANTIC STATES EARLY THIS
MORNING WILL LOSE ITS GRIP ON OUR WEATHER DURING THE COURSE OF TODAY
AS A VERY ROBUST SHORTWAVE WILL CHARGE SOUTHEAST ACROSS THE UPPER
GREAT LAKES. AN ANOMALOUSLY STRONG H25 JET OF 145KTS (RETURN
INTERVAL OF ONCE IN A 10-20 YR PERIOD) WILL ACCOMPANY THE DIGGING
MID LEVEL DISTURBANCE...LEADING TO A DEEP LONGWAVE TROUGH AND
EVENTUAL CLOSED LOW OVER NEW ENGLAND. AT THE SFC...A COLD FRONT WILL
SWEEP ACROSS OUR REGION LATER THIS AFTERNOON...FOCUSING THE LOW
LEVEL LIFT FOR THE EXPECTED SHOWER ACTIVITY.

AS WAS EXCELLENTLY DESCRIBED IN A PREVIOUS DISCUSSION...A SHARP MID
LEVEL TROUGH WILL DIG TOWARDS THE ST LAWRENCE VALLEY THIS
AFTERNOON...WITH AN ASSOCIATED COLD FRONT PUSHING SOUTHEAST ACROSS
THE REGION. THE STRONGEST LARGE SCALE ASCENT WILL CROSS THE NORTH
COUNTRY DURING THE AFTERNOON WITH A PERIOD OF STRONG DPVA AHEAD OF
THE SHORTWAVE AND UPPER LEVEL DIVERGENCE WITHIN THE LEFT EXIT REGION
OF A 150+ KNOT UPPER LEVEL JET AND AREA OF DIFFLUENT FLOW ALOFT.
PWAT VALUES RISE TO AROUND 1 INCH JUST AHEAD OF THE FRONT...MORE
THAN AMPLE FOR LATE FALL. THIS SHOULD ALL COME TOGETHER WITH LOW
LEVEL CONVERGENCE ALONG THE ADVANCING COLD FRONT TO PRODUCE A 3 HOUR
PERIOD OF SHOWERS ACROSS THE NORTH COUNTRY. THE LIFTED INDEX DROPS
TO -1C TO -3C DEPENDING ON MODEL OF CHOICE ACROSS THE NORTH
COUNTRY...AND THIS MARGINAL INSTABILITY COMBINED WITH STRONG FORCING
MAY PRODUCE A FEW SCATTERED WEAK THUNDERSTORMS AS WELL. FARTHER
SOUTHWEST ALONG THE TRAILING COLD FRONT LARGE SCALE ASCENT WILL BE
MUCH WEAKER...SO EXPECT SHOWERS TO REMAIN WIDELY SCATTERED ACROSS
THE REST OF THE AREA DURING THE MID TO LATE AFTERNOON. CLOUDS WILL
INCREASE ONCE AGAIN DURING THE AFTERNOON ALONG AND BEHIND THE
SURFACE COLD FRONT AS MOISTURE BECOMES TRAPPED BENEATH THE FRONTAL
INVERSION.

IT WILL BECOME WINDY TODAY AS WELL...ESPECIALLY NORTHEAST OF LAKE
ERIE IN A CORRIDOR FROM THE NIAGARA FRONTIER TO ROCHESTER WHERE
BUFKIT MOMENTUM TRANSFER SCHEMES SUGGEST SOUTHWEST WIND GUSTS IN THE
35-40 MPH RANGE DURING THE AFTERNOON. WHILE WINDY...THE STRONG SFC
PRESSURE GRADIENT IN ADVANCE OF THE FRONT WILL ADVECT A NARROW
TONGUE OF 7/8C H85 TEMPS ACROSS OUR REGION...AND THIS WILL SUPPORT
AFTERNOON TEMPS OF 60 TO 65...WITH UPPER 60S POSSIBLE ACROSS THE
GENESEE VALLEY AND FINGER LAKES REGION. THESE TEMPERATURES WILL BE
10 TO 15 DEG F ABOVE NORMAL VALUES.

IN THE WAKE OF THE COLD FRONT...MUCH CHILLIER AIR WILL POUR ACROSS
THE LOWER GREAT LAKES TONIGHT. H85 TEMPS WILL DROP TO ARND -1C AND
THIS WILL BE ESTABLISH ENOUGH INSTABILITY OVER LAKE ONTARIO TO
SUPPORT SOME LAKE EFFECT RAIN SHOWERS IN THE VCNTY OF THE TUG HILL.
THE MESOSCALE BASED PCPN WILL BE ENHANCED BY THE PASSING OF A VERY
STRONG SHORTWAVE TOWARDS SUNDAY MORNING...WHEN THE SHOWERS ARE
EXPECTED TO `BLOSSOM` NORTHWARDS TOWARDS THE THOUSAND ISLANDS.
WHILE THE PCPN IS EXPECTED TO FALL AS RAIN...THERE WILL BE ENOUGH
SYNOPTIC MOISTURE ABV 10K FT WITHIN THE DENDRITIC CRYSTAL GROWTH
ZONE TO PRODUCE SOME WET FLAKES. THE LOWEST FEW THOUSAND FEET OF THE
PROFILE THOUGH SHOULD BE FAR ENOUGH ABV FREEZING TO ALLOW ANY SNOW
TO MELT. THE EXCEPTION COULD BE ACROSS THE TUG HILL WHERE SOME WET
SNOW COULD MIX IN...BUT WILL HOLD OFF FROM ADDING THIS TO THE
PACKAGE.

OFF LK ERIE...THERE WILL BE A SERIOUS LACK OF SYNOPTIC MOISTURE ABV
5K FT SO AM NOT EXPECTING ANYTHING MORE THAN SOME LAKE INDUCED CLOUD
COVER. ELSEWHERE ACROSS WESTERN NEW YORK...TONIGHT WILL FEATURE BRISK
WINDS AND PARTLY CLOUDY SKIES.

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
ON SUNDAY...A DEEP CLOSED LOW OVER SOUTHERN QUEBEC WILL MEANDER ITS
WAY EASTWARD INTO THE CANADIAN MARITIMES...WHILE A COOL WESTERLY TO
WEST-NORTHWESTERLY FLOW PERSISTS ACROSS THE LOWER GREAT LAKES
REGION. A STRONG SHORTWAVE DROPPING THROUGH THE BACKSIDE OF THE
AFOREMENTIONED UPPER LEVEL CIRCULATION WILL ACT IN CONCERT WITH LAKE
AND OROGRAPHIC ENHANCEMENT TO BRING A PERIOD OF SHOWERS TO AREAS
EAST AND EAST-SOUTHEAST OF LAKE ONTARIO DURING THE MORNING...FOR
WHICH POPS HAVE BEEN RAISED TO CATEGORICAL GIVEN THE FAVORABLE
SYNOPTIC AND MESOSCALE SETUP. AFTER THAT TIME...INCREASING
SUBSIDENCE AND DRYING IN THE WAKE OF THE SHORTWAVE AND IN
CONJUNCTION WITH BUILDING SURFACE-BASED RIDGING SHOULD RESULT IN
THIS ACTIVITY GRADUALLY WEAKENING AND BEING INCREASINGLY DRIVEN MORE
BY LAKE AND OROGRAPHIC PROCESSES SUNDAY AFTERNOON...BEFORE
EVENTUALLY DYING OUT ALTOGETHER SUNDAY NIGHT.

ELSEWHERE...CONDITIONS SHOULD LARGELY BE DRY SUNDAY AND SUNDAY NIGHT
WITH JUST A STRAY SHOWER OR TWO POSSIBLE DOWNWIND OF LAKE ERIE AND
AROUND THE PERIPHERY OF THE AFOREMENTIONED AREA OF SHOWERS. EXPECT A
BREEZY DAY ON SUNDAY WITH THE COMBINATION OF GOOD MECHANICAL MIXING
AND 850 MB TEMPS OF ZERO TO -2C YIELDING HIGHS IN THE LOWER TO MID
50S IN MOST PLACES...FOLLOWED BY DIMINISHING WINDS AND TEMPS
DROPPING INTO THE MID 30S TO LOWER 40S SUNDAY NIGHT AS HIGH PRESSURE
BUILDS DIRECTLY OVERHEAD.

DURING MONDAY...THE AXIS OF THE SURFACE RIDGE WILL SLOWLY DRIFT EAST
INTO EASTERN NEW YORK AND NEW ENGLAND...WHILE DEVELOPING COMPLEX LOW
PRESSURE OVER THE NORTHERN PLAINS STATES PUSHES ITS ATTENDANT WARM
FRONT IN OUR DIRECTION. AT THIS JUNCTURE...EXPECT THIS LATTER
FEATURE TO APPROACH SLOWLY ENOUGH TO ALLOW FOR A DRY DAY...THOUGH
THE OVERALL WARM ADVECTION PATTERN WILL LIKELY RESULT IN A GENERAL
WEST TO EAST INCREASE IN CLOUD COVER OVER TIME...PARTICULARLY DURING
THE AFTERNOON HOURS. IN SPITE OF THIS INCREASE IN CLOUD COVER...OUR
AIRMASS SHOULD WARM ENOUGH TO PUSH TEMPERATURES TO AROUND THE 60
DEGREE MARK ACROSS THE BULK OF THE REGION SOUTH OF LAKE ONTARIO...
WHILE THE NORTH COUNTRY SHOULD REMAIN COOLER WITH HIGHS REMAINING
CONFINED TO THE LOWER TO MIDDLE 50S.

MONDAY NIGHT AND EARLY TUESDAY...THE COMPLEX LOW PRESSURE SYSTEM
OVER THE NORTHERN PLAINS WILL CONSOLIDATE AND STRENGTHEN WHILE
BODILY LIFTING NORTHEASTWARD INTO CENTRAL ONTARIO PROVINCE...AND IN
THE PROCESS WILL DRIVE ITS WARM FRONT NORTHEASTWARD ACROSS OUR
REGION. COUPLED WITH INCREASING LOW LEVEL CONVERGENCE AT THE NOSE OF
A DEVELOPING 30-35 KNOT LOW LEVEL JET...THE FRONTAL BOUNDARY WILL
PROBABLY BRING AT LEAST A LOWER-END RISK FOR SOME SHOWERS AS IT
TRAVERSES THE AREA FROM SOUTHWEST TO NORTHEAST...FOR WHICH SOME
CHANCE POPS WILL BE IN PLAY. TEMPERATURE-WISE...THE OVERALL WARM AIR
ADVECTION REGIME AND INCREASED CLOUD COVER WILL RESULT IN MONDAY
NIGHT BEING NOTICEABLY MILDER COMPARED TO ITS PREDECESSOR...WITH
LOWS RANGING FROM THE MID 40S ACROSS THE NORTH COUNTRY TO THE MID
AND POSSIBLY EVEN UPPER 50S ACROSS THE LAKE PLAINS OF FAR WESTERN
NEW YORK.

FOLLOWING THE PASSAGE OF THE WARM FRONT...WESTERN AND NORTH CENTRAL
NEW YORK APPEARS AS IF IT WILL BE ENTRENCHED IN THE WARM SECTOR OF
THE DEEPENING LOW THROUGH AT LEAST THE EARLY TO MID AFTERNOON HOURS
OF TUESDAY. AFTER THAT TIME...THE TRAILING COLD FRONT SHOULD
APPROACH AND CROSS THE REGION SOMETIME BETWEEN LATE TUESDAY
AFTERNOON AND TUESDAY NIGHT...WITH THE VARIOUS GUIDANCE PACKAGES
GENERALLY TRENDING A BIT SLOWER AGAIN WITH THE 00Z/25 CYCLE...WHILE
ALSO STILL EXHIBITING SOME DIFFERENCES WITH RESPECT TO THE TIMING OF
THE FRONT. WITH THE ABOVE IN MIND...HAVE SLOWED DOWN THE PASSAGE OF
THE FRONT A LITTLE BIT FROM OUR PREVIOUS CONTINUITY...WHILE ALSO
KEEPING SHOWER CHANCES CONFINED TO THE CHANCE RANGE GIVEN THE
CONTINUED UNCERTAINTY IN ITS TIMING.

WITH RESPECT TO TEMPERATURES...THESE LOOK AS IF THEY MAY REALLY SOAR
WITHIN THE WARM SECTOR ON TUESDAY. WITH 925 MB TEMPS CLIMBING TO AS
HIGH AS +14C TO +18C IN CONJUNCTION WITH A SOUTH-SOUTHWESTERLY
DOWNSLOPE FLOW...AT THIS POINT FEEL THAT HIGHS SHOULD REACH TO
AROUND 70 OR SO ACROSS THE NORTH COUNTRY...AND TO THE LOWER TO EVEN
MID 70S SOUTH OF LAKE ONTARIO. SHOULD SUCH READINGS ACTUALLY COME TO
FRUITION...THE RECORD HIGHS FOR BUFFALO AND ROCHESTER FOR OCTOBER
28TH (74/1946 AND 76/1984 RESPECTIVELY) COULD BE CLOSELY
APPROACHED...WHILE WATERTOWN`S RECORD HIGH (75/1984) WOULD BE MORE
LIKELY TO REMAIN SAFE. AFTER THAT...READINGS SHOULD FALL BACK INTO
THE UPPER 40S TO LOWER 50S FOLLOWING THE COLD FRONTAL PASSAGE
TUESDAY NIGHT.

&&

.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
IN THE WAKE OF TUESDAY NIGHT`S COLD FRONT...BROAD LARGE-SCALE
TROUGHING AND PROGRESSIVELY COOLER AIR WILL BECOME RE-ESTABLISHED
ACROSS THE GREAT LAKES AND NORTHEAST THROUGH THE REMAINDER OF THE
WEEK. WITH RESPECT TO TEMPERATURES...THIS WILL RESULT IN A
NOTICEABLE COOLING TREND THROUGH THE PERIOD...WITH READINGS
EVENTUALLY FALLING BACK BELOW NORMAL LEVELS BY THE END OF THE WORK
WEEK. MORE SPECIFICALLY...DAYTIME HIGHS AVERAGING IN THE MID TO
UPPER 50S ON WEDNESDAY WILL LIKELY DROP BACK TO THE MID AND UPPER
40S BY FRIDAY...WHILE DAYTIME HIGHS PULL BACK TO THE MID 30S TO
LOWER 40S.

AS FOR PRECIPITATION CHANCES...MOST AREAS SHOULD EXPERIENCE MAINLY
DRY WEATHER WEDNESDAY THROUGH THURSDAY...WITH JUST SOME NUISANCE
WEAK LAKE EFFECT RAIN SHOWERS FOUND EAST/EAST-SOUTHEAST OF THE
LAKES. AFTER THIS...THE MEDIUM RANGE GUIDANCE IS IN GENERAL
AGREEMENT ON SOME SEMBLANCE OF ANOTHER WEAK SYNOPTIC-SCALE SYSTEM
AFFECTING OUR REGION LATE IN THE PERIOD...THOUGH THE DETAILS VARY
FROM ONE PACKAGE TO THE NEXT. NONETHELESS...THIS SHOULD TRANSLATE
INTO A RENEWED GENERAL CHANCE OF SHOWERS IN TIME FOR THURSDAY NIGHT
AND FRIDAY...FOR WHICH SOME BROADBRUSH LOW CHANCE POPS WILL BE IN
PLAY.

&&

.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE NOSING NORTHWARDS FROM THE UPPER OHIO VALLEY WILL KEEP
VFR CONDITIONS IN PLACE FOR MOST AREAS THROUGH THE REMAINDER OF THE
PRE DAWN HOURS...ALTHOUGH SOME MVFR CIGS ARE POSSIBLE OVER PARTS OF
WRN NEW YORK.

A COLD FRONT OVER SOUTHERN ONTARIO WILL THEN PUSH SOUTHEAST AND
CROSS WESTERN AND NORTH CENTRAL NEW YORK LATER THIS AFTERNOON AND
EVENING. WHILE VFR CONDITIONS WILL PREVAIL FOR THE BULK OF THE
DAY...CIGS COULD BRIEFLY LOWER TO MVFR IN SHOWERS DURING THE FRONTAL
PASSAGE. IT WILL BECOME RATHER WINDY TODAY AS WELL WITH SOUTHWEST
SFC WINDS INCREASING TO 15 TO 30 KNOTS FOR MOST OF THE TAF SITES.

IN THE WAKE OF THE FRONT TONIGHT...VFR CONDITIONS WILL BE FOUND
ACROSS ALL OF WESTERN NEW YORK. THERE WILL BE SOME LAKE EFFECT RAIN
SHOWERS EAST OF LK ONTARIO THOUGH...AND THIS COULD RESULT IN MVFR
CONDITIONS FOR KART AND KGTB.

OUTLOOK...
SUNDAY...MAINLY VFR...EXCEPT AREAS OF MVFR EAST AND SOUTHEAST OF
LAKE ONTARIO WITH SHOWERS LIKELY.
MONDAY...MAINLY VFR.
TUESDAY...VFR/MVFR WITH A CHANCE OF SHOWERS.
WEDNESDAY...MAINLY VFR EXCEPT MVFR WITH A CHANCE OF SHOWERS EAST OF
THE LAKES.

&&

.MARINE...
WINDS WILL FRESHEN OVER THE LOWER GREAT LAKES TODAY AS A COLD FRONT
OVER MICHIGAN WILL SWEEP ACROSS THE REGION LATER THIS AFTERNOON.
WINDS WILL INITIALLY INCREASE ACROSS LAKE ERIE WHERE A RELATIVELY
TIGHT SFC PRESSURE GRADIENT AHEAD OF THE FRONT WILL ENCOURAGE WINDS
TO REACH 30 KNOTS...WITH SOME GALE FORCE WIND GUSTS POSSIBLE BY LATE
AFTERNOON. WINDS WILL TAKE SEVERAL HOURS LONGER TO INCREASE ON LAKE
ONTARIO...ESPECIALLY EAST OF ROCHESTER.

TONIGHT IN THE WAKE OF THE FRONT...WINDS WILL VEER TO THE WEST WITH
HIGH END SMALL CRAFT ADVISORY CONDITIONS REMAINING IN PLACE. THIS
WILL ESPECIALLY BE THE CASE ON LAKE ONTARIO WHERE SUSTAINED WINDS
WILL INCREASE TO NEAR GALE FORCE OVER THE EASTERN HALF.

THE STRONG GUSTY WINDS WILL REMAIN IN PLACE OVER BOTH LAKES ERIE AND
ONTARIO ON SUNDAY...THEN AS HIGH PRESSURE DRIFTS ACROSS THE REGION
SUNDAY NIGHT...WINDS WILL GRADUALLY SUBSIDE. RELATIVELY LIGHT WINDS
AND NEGLIGIBLE WAVES WILL BE FOUND ON BOTH LAKES MONDAY AS THE SFC
RIDGE PASSES.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT SUNDAY FOR LEZ040-041.
         SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
         LEZ020.
         SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 8 AM
         EDT MONDAY FOR LOZ043>045.
         SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 5 AM EDT
         MONDAY FOR LOZ042.

&&

$$

SYNOPSIS...RSH
NEAR TERM...HITCHCOCK/RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...RSH
MARINE...RSH







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