Area Forecast Discussion
Issued by NWS Buffalo, NY

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FXUS61 KBUF 240802
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
402 AM EDT FRI OCT 24 2014

.SYNOPSIS...
LOW PRESSURE OFF THE NEW ENGLAND COASTLINE WILL LIFT OUT INTO THE
CANADIAN MARITIMES TODAY...WITH LEFTOVER CLOUDS FROM THE GENESEE
VALLEY EASTWARD GIVING WAY TO INCREASING AMOUNTS OF SUNSHINE.
ANOTHER LOW PRESSURE SYSTEM MOVING ACROSS EASTERN CANADA WILL THEN
PUSH A COLD FRONT ACROSS OUR REGION ON SATURDAY ALONG WITH SOME
SCATTERED SHOWERS...BEFORE SUNSHINE AND WARMER WEATHER RETURN EARLY
NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 08Z...REGIONAL SATELLITE IMAGERY CONTINUES TO SHOW A DICHOTOMY
IN CLOUD COVER ACROSS THE BUFFALO CWA...WITH MAINLY CLEAR SKIES THE
GENERAL RULE ACROSS FAR WESTERN NEW YORK...AND MOSTLY CLOUDY
CONDITIONS FOUND FROM THE GENESEE VALLEY EASTWARD. WITHIN THIS
LATTER AREA...AREA RADARS CONTINUE TO SUGGEST THE POTENTIAL FOR
SOME SPOTTY LIGHT SPRINKLES.

THE ONE EXCEPTION TO ALL THIS IS ACROSS FAR SOUTHWESTERN NEW YORK...
WHERE A SWATH OF MORE LIMITED LOW STRATUS CONTINUES TO BRUSH ACROSS
FAR SOUTHWESTERN CHAUTAUQUA COUNTY. THROUGH THE PREDAWN HOURS...
FURTHER UPSLOPING/NOCTURNAL COOLING MAY HELP THESE LOWER CLOUDS AND
PERHAPS SOME PATCHY FOG TO DEVELOP/EXPAND EASTWARD ACROSS THE
SOUTHERN TIER. ELSEWHERE...CONDITIONS SHOULD GENERALLY REMAIN AS
THEY ARE THROUGH SUNRISE...WITH THE LARGER SWATH OF CLOUDS PERHAPS
SHIFTING A LITTLE FURTHER EAST AS THE RESPONSIBLE COASTAL LOW DRIFTS
A LITTLE FURTHER AWAY...AND A SLOW BACKING OF THE LOW LEVEL FLOW
HELPS TO SPREAD SOMEWHAT DRIER AIR EASTWARD INTO THE GENESEE VALLEY.

THROUGH THE DAYLIGHT HOURS...WE SHOULD SEE A RETURN TO MOSTLY SUNNY
SKIES AREAWIDE...AS ANY EARLY MORNING FOG/LOW STRATUS ACROSS THE
SOUTHERN TIER MIXES OUT WITH DIURNAL HEATING...AND THE LEFTOVER
CLOUDS ACROSS CENTRAL AND EASTERN SECTIONS RECEDE EAST OF THE AREA
AS THEIR PARENT SURFACE LOW FINALLY LIFTS OUT INTO THE CANADIAN
MARITIMES...AND HIGH PRESSURE/DRIER AIR OVER THE OHIO VALLEY
RIDGES NORTHEASTWARD INTO NEW YORK STATE. WITH THE INCREASING
SUNSHINE AND 925 MB TEMPS RUNNING BETWEEN +6C AND +9C...HIGH TEMPS
SHOULD LARGELY REACH INTO THE 55 TO 60 DEGREE RANGE TODAY...WITH THE
COOLEST TEMPS FOUND ACROSS THE HIGHER TERRAIN...AND THE WARMEST
TEMPS LOCATED ACROSS THE NORMALLY WARMER INTERIOR PORTIONS OF THE
GENESEE VALLEY AND FINGER LAKES.

TONIGHT...THE AXIS OF SURFACE-BASED RIDGING WILL SLIDE FROM
SOUTHERN ONTARIO TO EASTERN NEW YORK. ON ITS BACKSIDE...THE
LOW-LEVEL FLOW WILL BECOME WESTERLY THROUGH THE LOWEST 5 KFT OR SO
OF THE ATMOSPHERE...AND THIS WILL HELP ADVECT INCREASING AMOUNTS
OF LOWER-LEVEL MOISTURE INTO OUR REGION FROM THE CENTRAL GREAT
LAKES. THIS WILL RESULT IN AN INCREASING LOW CLOUDS OVER TIME...
WITH THIS TREND MOST PRONOUNCED DURING THE OVERNIGHT HOURS.
OTHERWISE...THE NIGHT SHOULD REMAIN DRY WITH LOWS RANGING
THROUGH THE 40S. THE WARMEST OVERALL TEMPS WILL BE FOUND ALONG THE
LAKE ERIE SHORE...WHERE AN ONSHORE FLOW SHOULD HELP KEEP READINGS
FROM FALLING BELOW THE UPPER 40S.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
PACIFIC MODIFIED AIR WILL CONTINUE TO DOMINATE THE COUNTRY THROUGH
THIS PERIOD...AND AS A RESULT...TEMPERATURES WILL AVERAGE ABOVE LATE
OCTOBER NORMALS. AN UPPER LEVEL STORM SYSTEM OFF BRITISH COLUMBIA
WILL BE THE LATEST TO SUPPORT THIS PATTERN...AS IT WILL DIRECT A
DEEP PACIFIC FLOW ACROSS SOUTHERN CANADA AND THE LOWER 48. AS WAS
MENTIONED IN PREVIOUS DISCUSSIONS...ANY COLD AIR WILL REMAIN LOCKED
UP IN THE CANADIAN ARCTIC.

MEANWHILE ANOMALOUSLY WARM AIR OVER THE WESTERN CONUS AT THE START OF
THIS PERIOD WILL GRADUALLY ADVECT EAST WITHIN A PROGRESSIVE RIDGE.
THIS RIDGE WILL DEVELOP AS A DIRECT RESULT OF A VERY POTENT UPSTREAM
SHORTWAVE THAT WILL SLAM INTO THE WEST COAST EARLY IN THE WEEKEND.
THE RIDGE WILL PUSH EAST DURING REMAINDER OF THE WEEKEND AND EARLY
NEXT WEEK...AND THIS WILL HELP TO KEEP THE OVERALL FLOW PROGRESSIVE
OVER EASTERN CANADA AND THE LOWER GREAT LAKES. THE AMPLIFICATION OF
THIS RIDGE OVER EASTERN CANADA WILL EVENTUALLY LEAD TO NEAR RECORD
HIGHS IN THE LONG TERM PORTION OF THE FORECAST. MORE ON THIS IN THE
LONG TERM SECTION BELOW.

A PAIR OF POTENT SHORTWAVES RACING ACROSS THE CANADIAN PRAIRIES IN A
130KT H25 JET WILL DIG OUT A FRESH LONGWAVE TROUGH AND ASSOCIATED
CLOSED LOW OVER QUEBEC AS WE OPEN THIS PERIOD ON SATURDAY. A
CORRESPONDING SFC COLD FRONT WILL SWEEP ACROSS THE LOWER GREAT LAKES
IN THE PROCESS...BUT GIVEN THE LACK OF MOISTURE...THE DAY SHOULD BE
LARGELY PCPN FREE WITH ONLY SCT AFTERNOON AND EVENING SHOWERS WITH
QPF GENERALLY UNDER A TENTH OF AN INCH. THE ACTIVITY COULD BE A
LITTLE MORE WIDESPREAD ACROSS THE NORTH COUNTRY (NORTH OF TUG). WILL
LEAVE LOW LIKELY POPS FOR THAT AREA. TEMPS WILL CLIMB INTO THE LOW
TO MID 60S ACROSS THE LAKE PLAINS WITH 50S EXPECTED ACROSS THE
HIGHER TERRAIN.

SOMEWHAT CHILLY AIR WILL RACE ACROSS THE LOWER GREAT LAKES AND OUR
FORECAST AREA IN THE WAKE OF THE FRONT SATURDAY NIGHT. H85 TEMPS
WILL DROP BELOW ZERO C AND THIS WILL SET UP ENOUGH INSTABILITY OVER
THE LAKES TO GENERATE SOME NUISANCE LAKE EFFECT RAIN SHOWERS. THE
BULK OF THESE WILL BE EAST OF LK ONTARIO WHERE SYNOPTIC MOISTURE
WILL BE A LITTLE MORE ABUNDANT. OVER LAKE ERIE...A SERIOUS LACK OF
MOISTURE ABV 5K FT SHOULD PRECLUDE ANY LAKE DRIVEN SHOWERS...
ALTHOUGH FAIRLY STRONG CHANNELLED VORTICITY OVER THE REGION COULD
HELP TO GENERATE SOME SPRINKLES EARLY IN THE NIGHT. MIN TEMPS WILL
GENERALLY BE IN THE LOWER 40S.

IT WILL BE BRISK AND COOL ACROSS OUR REGION ON SUNDAY AS WE WILL
FIND OURSELVES SANDWICHED BETWEEN DEEP LOW PRESSURE OVER THE
CANADIAN MARITIMES AND HIGH PRESSURE OVER THE OHIO VALLEY. THIS WILL
PRODUCE A VERY COOL WEST TO NORTHWEST FLOW OF CANADIAN AIR (ALBEIT
PACIFIC MODIFIED) OVER OUR REGION WITH MOST AREAS EXPERIENCING A
FAIR AMOUNT OF SUN. THE EXCEPTION WILL BE EAST OF LK ONTARIO WHERE
AN UNSTABLE AIRMASS WILL BE FOUND UNDER THE CORE OF A STRONG UL JET.
ANY SHOWERS WILL BE ENHANCED NEAR OR SOUTH OF THE TUG FROM CONTINUED
MESOSCALE LAKE DRIVEN PROCESSES...WHICH BY THE WAY WILL WEAKEN AS
THE DAY PROGRESSES.

HIGH PRESSURE OVER THE OHIO VALLEY WILL THEN NOSE NORTH ACROSS OUR
FORECAST AREA SUNDAY NIGHT. THIS WILL ENSURE A FAIR DRY NIGHT ACROSS
THE REGION...WITH ANY LINGERING NUISANCE LAKE RAIN SHOWERS ENDING
EAST OF LK ONTARIO. TEMPERATURES WILL DROP OFF INTO THE 30S AND
LOWER 40S.

ON MONDAY...BROAD RIDGING WILL CROSS THE LOWER GREAT LAKES WHILE THE
ASSOCIATED SFC HIGH WILL DRIFT OFF THE COAST OF THE CAROLINAS. THE
ENSUING WARM ADVECTION OVER OUR REGION WILL GENERATE SOME HIGH AND
MID LEVEL CLOUDS DURING THE COURSE OF THE DAY...BUT A WEALTH OF DRY
AIR IN THE LOW LEVELS AND THE EXPECTATION THAT THE STRONGEST
ISENTROPIC LIFT WILL BE TO OUR NORTHWEST WILL RESULT IN A NICE DRY
DAY WITH TEMPERATURES REBOUNDING INTO THE 60S.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A PROGRESSIVE...SINUSOIDAL LONGWAVE PATTERN WILL REMAIN IN PLACE
ACROSS THE COUNTRY DURING THIS PERIOD...AND THIS WILL ENSURE THAT
NEAR TO ABOVE NORMAL TEMPERATURES WILL CONTINUE. THE WARMEST DAY
WILL BE RIGHT AT THE START OF THE PERIOD ON TUESDAY WHEN A BROAD
AMPLIFYING RIDGE OVER EASTERN CANADA WILL PUMP ANOMALOUSLY WARM AIR
ACROSS OUR REGION.

H85 TEMPS ARE PROJECTED TO CLIMB TO ARND 12C BY MIDDAY TUESDAY...
AND WHEN FULLY MIXED...THIS WOULD SUPPORT NEAR RECORD MAX TEMPS IN
THE LOW TO MID 70S. RECORDS FOR TUESDAY INCLUDE BUF 74 IN 1946...
ROC 76 IN 1984...AND WATERTOWN 75 ALSO IN 1984. THERE WILL BE A COLD
FRONT BEARING DOWN ON THE LOWER GREAT LAKES THOUGH...SO CLOUDS AND
SHOWERS ASSOCIATED WITH THIS SYSTEM COULD BRING A SCREECHING HALT TO
THE SOARING TEMPS. THE FRONT IS SOME 3-6 HOURS FASTER THAN PREVIOUS
GUIDANCE PACKAGES.

SHOWERS FROM THE FRONT WILL CROSS OUR REGION LATE TUESDAY AND
TUESDAY EVENING. MUCH COOLER AIR WILL POUR ACROSS THE LOWER GREAT
LAKES IN THE WAKE OF THE FRONT OVERNIGHT...AND THIS WILL ONCE AGAIN
SET UP THE CHANCE FOR A MINIMAL LAKE RESPONSE WITH SOME SHOWERS EAST
OF LK ONTARIO.

HIGH PRESSURE OVER THE OHIO VALLEY WILL BUILD ACROSS THE LOWER GREAT
LAKES WEDNESDAY AND THURSDAY NIGHT...WHILE A POOL OF PACIFICALLY
MODIFIED CANADIAN AIR WILL GLANCE BY TO OUR NORTH. THIS WILL
TRANSLATE INTO A PAIR OF SEASONABLY COOL DAYS WITH HIGHS IN THE
50S.

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
AS OF 08Z...REGIONAL SATELLITE IMAGERY CONTINUES TO SHOW A DICHOTOMY
IN CLOUD COVER ACROSS THE AREA...WITH MAINLY CLEAR SKIES THE GENERAL
RULE ACROSS FAR WESTERN NEW YORK...AND MOSTLY CLOUDY CONDITIONS
FOUND FROM THE GENESEE VALLEY EASTWARD. WITHIN THIS LATTER AREA...
LOWER-END VFR CEILINGS ARE GENERALLY DOMINANT...SAVE FOR SOME MVFR
CIGS ACROSS THE NORTH COUNTRY AND UPPER PORTIONS OF THE GENESEE
VALLEY.

THE ONE EXCEPTION TO ALL THIS IS ACROSS FAR SOUTHWESTERN NEW YORK...
WHERE A SWATH OF MORE LIMITED IFR STRATUS CONTINUES TO BRUSH ACROSS
FAR SOUTHWESTERN CHAUTAUQUA COUNTY. THROUGH THE PREDAWN HOURS...
FURTHER UPSLOPING/NOCTURNAL COOLING MAY HELP THESE LOWER CLOUDS AND
PERHAPS SOME PATCHY FOG TO DEVELOP/EXPAND EASTWARD ACROSS THE
SOUTHERN TIER. ELSEWHERE...CONDITIONS SHOULD GENERALLY REMAIN AS
THEY ARE THROUGH SUNRISE...WITH THE LARGER SWATH OF CLOUDS PERHAPS
SHIFTING A LITTLE FURTHER EAST AS THE RESPONSIBLE COASTAL LOW DRIFTS
A LITTLE FURTHER AWAY...AND A SLOW BACKING OF THE LOW LEVEL FLOW
HELPS TO SPREAD SOMEWHAT DRIER AIR EASTWARD INTO THE GENESEE VALLEY.

THROUGH THE DAYLIGHT HOURS...CONDITIONS SHOULD IMPROVE TO VFR
AREAWIDE...WITH ANY EARLY MORNING FOG/LOW STRATUS ACROSS THE
SOUTHERN TIER MIXING OUT WITH DIURNAL HEATING...AND LEFTOVER
CEILINGS ACROSS THE FINGER LAKES AND NORTH COUNTRY FINALLY RECEDING
EAST OF THE AREA IN CONJUNCTION WITH THEIR PARENT AREA OF LOW
PRESSURE.

TONIGHT...THE AXIS OF SURFACE-BASED RIDGING WILL SLIDE FROM SOUTHERN
ONTARIO TO EASTERN NEW YORK. ON ITS BACKSIDE...THE LOW-LEVEL FLOW
WILL BECOME WESTERLY THROUGH THE LOWEST 5 KFT OF THE ATMOSPHERE...
AND THIS WILL HELP ADVECT INCREASING AMOUNTS OF LOWER-LEVEL MOISTURE
INTO OUR REGION FROM THE CENTRAL GREAT LAKES. IN TURN...THIS WILL
LEAD TO AN INCREASE IN LOWER-END VFR CLOUD COVER OVER TIME...WITH
SOME MVFR CIGS PERHAPS EVEN DEVELOPING ACROSS THE HIGHER TERRAIN
LATE IN THE NIGHT.

OUTLOOK...
SATURDAY...VFR/MVFR WITH SCATTERED SHOWERS SOUTH OF LAKE
ONTARIO...AND MORE NUMEROUS SHOWERS ACROSS THE NORTH COUNTRY.
SUNDAY...MVFR/VFR WITH SCATTERED TO NUMEROUS SHOWERS EAST AND
SOUTHEAST OF LAKE ONTARIO.
MONDAY AND TUESDAY...MAINLY VFR.

&&

.MARINE...
LOW PRESSURE OFF THE NEW ENGLAND COAST WILL LIFT OUT INTO THE
CANADIAN MARITIMES TODAY...WHILE HIGH PRESSURE BUILDS NORTHEASTWARD
INTO THE LOWER GREAT LAKES FROM THE OHIO VALLEY. IN BETWEEN THESE
TWO SYSTEMS...A MODEST NORTHWESTERLY FLOW WILL BECOME MORE WESTERLY
TODAY AND BRIEFLY INCREASE ACROSS LAKE ONTARIO...BEFORE WEAKENING
AGAIN LATE THIS AFTERNOON AND THIS EVENING. WHILE IT IS NOT OUT OF
THE QUESTION THAT THIS COULD LEAD TO A BRIEF PERIOD OF LOW-END
ADVISORY-LEVEL CONDITIONS ACROSS CENTRAL AND EASTERN PORTIONS OF THE
LAKE...AT THIS TIME IT APPEARS THAT WINDS AND WAVES SHOULD REMAIN
BELOW ADVISORY CRITERIA AREAWIDE.

OVER THE WEEKEND...ANOTHER COLD FRONT WILL CROSS THE LOWER LAKES
REGION...AND SHOULD BE ACCOMPANIED BY ANOTHER SOLID ROUND OF
WIDESPREAD ADVISORY-LEVEL WINDS AND WAVES...BEGINNING SATURDAY
MORNING ON LAKE ERIE...AND SATURDAY AFTERNOON ON LAKE ONTARIO.

&&

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

&&

$$

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








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