Area Forecast Discussion
Issued by NWS Buffalo, NY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KBUF 010452
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1152 PM EST SAT JAN 31 2015

.SYNOPSIS...
COLD AIR WILL REMAIN ENTRENCHED ACROSS THE REGION FOR THE REST OF
TONIGHT WITH A FEW LINGERING SNOW SHOWERS OR PERHAPS POCKETS OF
FREEZING DRIZZLE. A WINTER STORM WILL IMPACT THE REGION BEGINNING
SUNDAY AND CONTINUING THROUGH MONDAY. THE HEAVIEST SNOW WITH THIS
SYSTEM IS EXPECTED SUNDAY AFTERNOON THROUGH MONDAY MORNING...WITH
BLOWING AND DRIFTING SNOW ALSO BECOMING A CONCERN SUNDAY NIGHT AND
MONDAY. ANOTHER ROUND OF BITTERLY COLD AIR WILL BUILD INTO THE
REGION MONDAY AND TUESDAY WITH DANGEROUSLY COLD WIND CHILLS
DEVELOPING.

&&

.NEAR TERM /THROUGH SUNDAY/...
A COLD FRONT WILL APPROACH FROM THE NORTH TONIGHT AND REACH THE NEW
YORK/PENNSYLVANIA STATE LINE BY SUNDAY MORNING...REINFORCING COLD
AIR ACROSS THE REGION. TEMPERATURES ALOFT MAY ONCE AGAIN BECOME COLD
ENOUGH IN THE DEVELOPING WEST NORTHWEST FLOW BEHIND THE FRONT TO
GENERATE SOME LIMITED LAKE RESPONSE SOUTHEAST OF THE LAKES. THIS MAY
BRING AN INCH OR TWO TO THESE AREAS. 00Z FORECAST PROFILES INDICATE
INCREASING MID LEVEL MOISTURE WITH THE FRONT AND CURRENT RADAR AND
SURFACE OBSERVATIONS INDICATE MAINLY LIGHT SNOW...AN OVERLAYING
MOIST LAYER AND DENDRITIC GROWTH ZONE SHOULD PROVIDE SEEDING FROM
ALOFT TO KEEP THE LIGHT PRECIP AS SNOW AND LOWER THE OUTSIDE CHANCE
OF LIGHT FREEZING DRIZZLE TO NEAR NIL.

SIGNIFICANT WINTER WEATHER EVENT LOOKS TO BE SHAPING UP FOR WESTERN
AND CENTRAL NEW YORK STARTING SUNDAY...BUT CURRENT THINKING IS THAT
THE MOST SIGNIFICANT IMPACTS WILL BE BEYOND THIS PORTION OF THE
FORECAST.

CONSENSUS OF THE 12Z MODEL SUITE ARRIVING A TOUCH NORTHWARD WITH THE
OVERALL DOWNSTREAM FORECAST OF THE STORM SYSTEM. THIS HAS REQUIRED
AN ADJUSTMENT THAT TRANSLATES INTO A GENERAL NORTHWARD SHIFT TO
OVERALL FORECASTER CONFIDENCE AND UNIFORM UPWARD TREND IN THE
SNOWFALL ACCUMULATION POTENTIAL THROUGHOUT THE LOCAL AREA.

STEADY DEEPENING OF THE SHORTWAVE CURRENTLY SEEN ON WATER VAPOR
IMAGERY THIS EVENING ACROSS SOUTHEASTERN COLORADO WILL BE WELL
UNDERWAY SUNDAY MORNING ACROSS THE CENTRAL PLAINS...THIS PROCESS
MAGNIFIED AS THE TRAILING ANOMALY CATCHES THE ENERGY BEING SHEARED
OUT OF THE CLOSED LOW DRIFTING THROUGH THE SOUTHWEST CONUS. WATER
VAPOR IMAGERY PROVIDING AN IMPRESSIVE REPRESENTATION OF THE
AVAILABLE MOISTURE CONTENT CURRENTLY TIED TO THIS LOW...WITH A
SUBSTANTIAL MID LEVEL THETA-E/WARM AIR ADVECTION COMPONENT EMERGING
THROUGH THE PLAINS. THIS WILL RESULT IN AN AGGRESSIVE NORTHEASTWARD
EXPANSION OF THIS MOISTURE PLUME THROUGH THE OHIO VALLEY INTO
WESTERN NEW YORK DURING THE DAY SUNDAY.

SNOWFALL AMOUNTS MAY BE TEMPERED A BIT INITIALLY BY THE PRESENCE OF
DRY AIR IN PLACE ACROSS THE AREA...BUT EXPECTED BY SUNDAY AFTERNOON
STEADY SNOW WILL BE OCCURRING ACROSS THE WESTERN HALF OF THE AREA.
NEARLY ALL GUIDANCE SUGGESTING A 1-3 INCH ACCUMULATION BY THE END OF
THE DAY SUNDAY ACROSS THE WESTERN THIRD OF THE AREA WITH THE HIGHER
AMOUNTS FOCUSED SOUTH OF THE THRUWAY.

THE EVENT WILL THEN TAKE OFF AFTER THIS POINT SUNDAY NIGHT.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH WEDNESDAY NIGHT/...
IN THIS PERIOD...THE MAIN PERIOD OF CONCERN WILL BE SUNDAY NIGHT AND
MONDAY...WHEN A SIGNIFICANT WINTER STORM WILL TRACK FROM THE OHIO
VALLEY EASTWARD ALONG THE MASON-DIXON LINE...AND EVENTUALLY OFF THE
NEW JERSEY COASTLINE. THE 12Z SUITE OF MODEL GUIDANCE HAS CONTINUED
THE TRENDS TOWARD A STRONGER OVERALL SYSTEM AND A MORE NORTHERLY
TRACK THAT BEGAN A COUPLE OF NIGHTS AGO...WITH MOST OF THE
OPERATIONAL MODELS NOW TIGHTLY CLUSTERED ALONG THE AFOREMENTIONED
TRACK...AND CONSEQUENTLY BRINGING HEAVIER PRECIPITATION EVEN FURTHER
NORTHWARD INTO WESTERN AND CENTRAL NEW YORK...A SCENARIO WHICH
CERTAINLY LOOKS REASONABLE GIVEN THE DEEP MOISTURE AND STRONG
SYNOPTIC-SCALE LIFT THAT WILL BE ACCOMPANYING THIS SYSTEM. AT THIS
POINT...THE BULK OF THE HEAVIER SNOW LOOKS TO FALL BETWEEN SUNDAY
NIGHT AND MONDAY MORNING...WITH THIS THEN TAPERING OFF FROM WEST TO
EAST AS THE SYSTEM PULLS AWAY MONDAY AFTERNOON.

IN TERMS OF PRECIPITATION AMOUNTS...A CONSENSUS OF WPC GUIDANCE AND
QPF FROM THE MAIN OPERATIONAL MODELS SUGGESTS THAT TOTAL LIQUID
EQUIVALENT AMOUNTS FOR SUNDAY NIGHT AND MONDAY WILL RANGE FROM
AROUND THREE QUARTERS OF AN INCH ALONG THE NY-PA BORDER TO AROUND
FOUR TENTHS OF AN INCH ALONG A LINE RUNNING FROM THE SOUTHERN SHORE
OF LAKE ONTARIO EASTWARD TO SOUTHERN LEWIS COUNTY...WITH AMOUNTS
THEN SHARPLY DIMINISHING TO AROUND A TENTH OF AN INCH ACROSS THE
SAINT LAWRENCE VALLEY. GIVEN LIKELY SNOWFALL:LIQUID RATIOS OF AROUND
15:1 SUNDAY NIGHT INCREASING TO AROUND 20:1 DURING MONDAY AS COLDER
AIR WRAPS IN BEHIND THE DEPARTING LOW CENTER...SUCH AMOUNTS WILL
ALMOST CERTAINLY TRANSLATE INTO STORM TOTAL ACCUMULATIONS OF 10 TO
14 INCHES ACROSS OUR SOUTHERNMOST TWO TIERS OF ZONES...WHERE THE
INITIAL ROUND OF WINTER STORM WATCHES HAVE CONSEQUENTLY BEEN
UPGRADED TO WINTER STORM WARNINGS.

SUPPORTING THE HIGHER END OF THE 10 TO 14 INCH SNOW ACCUMULATION
RANGE WILL BE VERY FAVORABLE MICROPHYSICS...INCLUDING A 7 TO NEARLY
10K FT DEEP DENDRITIC GROWTH ZONE AT THE PEAK OF THE EVENT AND A 5K
FT DEEP ISOTHERMAL LAYER CLOSER TO THE SFC THAT WILL MAXIMIZE GROWTH
THROUGH RIMING. COULD ENVISION TOTALS OF A FOOT AND A HALF ACROSS
THE SOUTHERN TIER AND PORTIONS OF THE FINGER LAKES IF THIS THERMAL
PROFILE WERE TO VERIFY.

NORTH OF THIS...TOTAL ACCUMULATIONS SHOULD BE SOMEWHAT LOWER DUE TO
INCREASING NORTHWARD EXTENT FROM THE TRACK OF THE LOW...HOWEVER
ACCUMULATIONS OF 6 TO 12 INCHES STILL APPEAR QUITE POSSIBLE FROM THE
NIAGARA FRONTIER EASTWARD ACROSS THE ROCHESTER AREA/NORTHERN FINGER
LAKES TO OSWEGO AND LEWIS COUNTIES. THIS WILL ESPECIALLY BE THE CASE
DIRECTLY SOUTH OF LAKE ONTARIO...WHERE ADDITIONAL LAKE AND
OROGRAPHIC ENHANCEMENT MAY ALSO COME INTO PLAY ON MONDAY AS A
NORTHERLY FLOW OF COLDER AIR DEVELOPS AROUND THE BACKSIDE OF THE
DEPARTING SYSTEM. WITH FORECAST CONFIDENCE IN HEAVIER SNOWFALL
AMOUNTS FOR THESE AREAS INCREASING THOUGH NOT YET QUITE HIGH ENOUGH
FOR A WINTER STORM WARNING GIVEN THE STILL-CLOSE PROXIMITY TO THE
NORTHERN EDGE OF THE SYSTEM...ADDITIONAL WINTER STORM WATCHES WERE
HOISTED EARLIER THIS AFTERNOON TO HIGHLIGHT THIS POTENTIAL. SHOULD
THE CURRENT EXPECTATIONS FOR THIS SYSTEM HOLD THOUGH...EXPECT
THAT AN EVENTUAL UPGRADE TO WINTER STORM WARNINGS FOR THESE AREAS
WILL LIKELY FOLLOW SOMETIME LATER ON TONIGHT OR EARLY SUNDAY
MORNING.

AT THIS POINT...THE ONLY PART OF OUR CWA NOT CURRENTLY UNDER A
WINTER WEATHER HEADLINE IS JEFFERSON COUNTY...WHERE TOTAL SNOWFALL
AMOUNTS CURRENTLY LOOK TO REMAIN CONFINED TO THE ADVISORY RANGE OR
LOWER. THIS STATED...SHOULD SUCH SNOWFALL AMOUNTS STILL APPEAR
LIKELY AS WE DRAW CLOSER TO THE EVENT...A WINTER WEATHER ADVISORY
WOULD ULTIMATELY BECOME NECESSARY FOR THIS AREA AS WELL.

AS THE CYCLONIC FLOW AROUND THIS SYSTEM STRENGTHENS SUNDAY NIGHT AND
EARLY MONDAY...AREAS OF BLOWING AND DRIFTING SNOW WILL ALSO BECOME A
CONCERN...PARTICULARLY ALONG AND INLAND FROM THE SOUTHERN SHORES OF
LAKES ERIE AND ONTARIO WHERE WINDS WILL BE THE STRONGEST DUE TO THE
ONSHORE COMPONENT TO THE LOW LEVEL FLOW. TEMPERATURES WILL ALSO RUN
WELL BELOW AVERAGE FOR THE MOST PART...WITH LOWS RANGING FROM AROUND
10 ABOVE ACROSS THE SOUTHERN TIER TO THE NEGATIVE SINGLE DIGITS
ACROSS THE NORTH COUNTRY SUNDAY NIGHT...AND HIGHS ON MONDAY THEN
STRUGGLING TO REACH THE 10 TO 15 RANGE...IF THAT.

FOLLOWING THE DEPARTURE OF THIS SYSTEM...MONDAY NIGHT AND TUESDAY
WILL FEATURE QUIETER AND MUCH DRIER WEATHER FOR MOST PLACES AS THE
AXIS OF SURFACE-BASED RIDGING AND MUCH DRIER AIR SLIDES FROM THE
CENTRAL GREAT LAKES EASTWARD ACROSS NEW YORK STATE...WHILE A
DEVELOPING CLIPPER SYSTEM TAKES SHAPE ACROSS THE CENTRAL GREAT LAKES
AND ONTARIO PROVINCE. THE ONE EXCEPTION TO THIS WILL BE DOWNWIND OF
LAKE ONTARIO...WHERE ENOUGH MOISTURE WILL STILL BE IN PLACE TO
SUPPORT SOME SCATTERED LIGHT LAKE EFFECT SNOW SHOWERS. THESE WILL
INITIALLY BE LOCATED SOUTH OF THE LAKE MONDAY NIGHT...BEFORE
SHIFTING NORTHWARD ACROSS THE NORTH COUNTRY AND INTO THE SAINT
LAWRENCE VALLEY ON TUESDAY AS THE LARGE-SCALE FLOW BACKS WITH THE
PASSAGE OF THE SURFACE RIDGE AXIS...AND IN ADVANCE OF THE DEVELOPING
CLIPPER SYSTEM.

AFTER THAT...THE REMAINDER OF THE PERIOD WILL THEN FEATURE THE
APPROACH AND PASSAGE OF THE AFOREMENTIONED CLIPPER...WITH THIS
LIKELY CENTERING AROUND THE DAYLIGHT HOURS OF WEDNESDAY. THIS SYSTEM
NOW APPEARS STRONG ENOUGH IN THE BULK OF THE MEDIUM RANGE GUIDANCE
TO WARRANT BUMPING SNOW SHOWER PROBABILITIES UP INTO THE LIKELY
RANGE ON WEDNESDAY...WITH PERIODS OF CHANCE POPS FLANKING THIS
TUESDAY NIGHT AND WEDNESDAY NIGHT.

WITH RESPECT TO TEMPERATURES...IT WILL REMAIN RATHER COLD MONDAY
NIGHT WITH ARCTIC AIR REMAINING IN PLACE...WHEN LOWS SHOULD RANGE
FROM WITHIN A FEW DEGREES OF ZERO SOUTH OF LAKE ONTARIO TO THE MID
NEGATIVE TEENS ACROSS THE NORTH COUNTRY...WITH COLDER TEMPS THAN
THIS NOT OUT OF THE QUESTION. THIS WOULD ESPECIALLY BE THE CASE
SHOULD ANY NOTEWORTHY CLEARING MANAGE TO DEVELOP...WHICH WOULD ALLOW
READINGS TO REALLY PLUMMET GIVEN THE PRESENCE OF THE FRESH DEEP
SNOWPACK LEFT BEHIND BY THE WINTER STORM. AFTER THAT...A GENERAL
WARM AIR ADVECTION PATTERN WILL SET UP ACROSS THE AREA OUT AHEAD OF
THE APPROACHING CLIPPER...WHICH SHOULD ALLOW HIGHS TO RECOVER INTO
THE MID TEENS TO LOWER 20S ON TUESDAY AND POTENTIALLY AS HIGH AS THE
UPPER 20S AND LOWER 30S ON WEDNESDAY...BEFORE READINGS FALL OFF
AGAIN WEDNESDAY NIGHT WITH THE ARRIVAL OF A FRESH BATCH OF ARCTIC
AIR IN THE WAKE OF THE DEPARTING CLIPPER.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
TEMPERATURES WILL REMAIN WELL BELOW NORMAL FOR THE BULK OF THIS
PERIOD...AS A RELATIVELY SHALLOW LONGWAVE TROUGH OVER EASTERN NORTH
AMERICA WILL KEEP VERY COLD AIR IN PLACE. THIS WILL ESPECIALLY BE
THE CASE THURSDAY AND FRIDAY WHEN MAX TEMPS IN MOST AREAS WILL NOT
CLIMB OUT OF THE TEENS.

WHILE IT WILL CERTAINLY BE COLD DURING THIS PERIOD...WE ARE NOT
EXPECTING A LOT OF SNOW. SOME NUISANCE LAKE SNOW WILL BE FOUND
MAINLY SOUTHEAST OF BOTH LAKES ERIE AND ONTARIO FOR THURSDAY...BUT
WITH AN ARCTIC SFC HIGH CRUISING ACROSS OUR REGION...THERE WILL BE A
WEALTH OF SYNOPTIC DRY AIR ABOVE 6K FT AND A MODERATE TO HIGH AMOUNT
OF SHEAR UNDER THE CAP.

A COLLAPSING CAP THURSDAY NIGHT WILL THEN WEAKEN AN ALREADY
UNIMPRESSIVE LAKE RESPONSE AS RESIDUAL LAKE SNOWS WILL BE FOCUSED
WITHIN 25 MILES OR SO OF THE SOUTHERN SHORE OF LK ONTARIO. OTHERWISE
THURSDAY NIGHT WILL BE FRIGID WITH THE MERCURY DROPPING INTO THE
SINGLE DIGITS FOR THE VAST MAJORITY OF THE FORECAST AREA.

AS THE HIGH PUSHES EAST ON FRIDAY...UNEVENTFUL WEATHER IS
ANTICIPATED ACROSS WESTERN NEW YORK. SOME SNOW SHOWERS WILL BE
POSSIBLE EAST OF LK ONTARIO...WITH ONLY FLURRIES POSISBLE ELSEWHERE.

THE NEXT STRONG SFC HIGH OVER ONTARIO WILL THEN PUSH A COLD FRONT
ACROSS THE LOWER GREAT LAKES FRIDAY NIGHT AND/OR EARLY SATURDAY.
THIS SHOULD PRODUCE A ROUND OF SNOW SHOWERS OF OUR REGION...BUT AT
THIS POINT NOTHING SIGNIFICANT IS EXPECTED.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
EXPECT MVFR CIGS THROUGH THE NIGHT AS A COLD FRONT CROSSES THE
REGION...ALONG WITH LIGHT SNOW OR FLURRIES WHICH SHOULD NOT AFFECT
VISIBILITY APPRECIABLY. STRONG WINTER STORM APPROACHING FROM THE
MIDWEST WILL BRING A PROLONGED PERIOD OF IFR CONDITIONS STARTING
DURING THE LATE AFTERNOON...FALLING TO LIFR DURING SUNDAY EVENING
AND NIGHT. THE EXCEPTION WILL BE KART AND THE NORTH COUNTRY WHERE
LOWER CEILINGS AND HEAVIER SNOW WILL NOT REACH AS FAR TO THE NORTH
AND MVFR CIGS TONIGHT WILL GIVE WAY TO VFR CONDITIONS ON SUNDAY.

OUTLOOK...
SUNDAY...VFR/MVFR EARLY THEN IFR SPREADING FROM SW TO NE.
SUNDAY NIGHT AND MONDAY...IFR/LIFR IN SNOW IN MOST AREAS...VFR WITH
A CHANCE OF SNOW AT ART.
TUESDAY...VFR/MVFR. A CHANCE OF SNOW SHOWERS EAST OF LAKE ONTARIO.
WEDNESDAY...VFR/MVFR. A CHANCE OF SNOW SHOWERS.

&&

.MARINE...
HIGH PRESSURE MAINTAINING LIGHT WINDS THIS EVENING WILL MOVE EAST
TONIGHT. A COLD FRONT WILL DROP ACROSS THE LAKES LATER TONIGHT WITH
AN INCREASING WESTERLY FLOW BEHIND IT. LOW PRESSURE WILL TRACK TO
THE SOUTH OF THE LAKES SUNDAY NIGHT AND EARLY MONDAY WITH AN
INCREASING NORTHEASTERLY FLOW...POSSIBLY PRODUCING SMALL CRAFT
CONDITIONS ON LAKE ONTARIO. WINDS WILL TURN NORTHWESTERLY BY MONDAY
NIGHT AS THE LOW TRACKS TO THE EAST AND HIGH PRESSURE APPROACHES
FROM THE WEST. WIND SPEEDS MAY REMAIN STRONG ENOUGH TO CONTINUE A
SMALL CRAFT RISK ON LAKE ONTARIO AS WELL AS FREEZING SPRAY
CONCERNS.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WINTER STORM WATCH FROM SUNDAY EVENING THROUGH MONDAY EVENING
     FOR NYZ003>006-008.
     WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
     AFTERNOON FOR NYZ001-002.
     WINTER STORM WARNING FROM 7 AM SUNDAY TO 4 PM EST MONDAY FOR
     NYZ010>014-019>021-085.
MARINE...NONE.

&&

$$

SYNOPSIS...TMA
NEAR TERM...TMA/WCH
SHORT TERM...JJR/RSH
LONG TERM...RSH
AVIATION...TMA/WCH
MARINE...TMA/WCH






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.