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 241140
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
640 AM EST MON NOV 24 2014

.SYNOPSIS...
WIDESPREAD RAIN WILL MOVE OUT OF THE AREA AND TEMPERATURES WILL
CONTINUE TO INCREASE AS A WARM FRONT CROSSES WESTERN AND
NORTH-CENTRAL NEW YORK. THE WARMING TEMPERATURES COMBINED WITH
INCREASINGLY STRONG WINDS TODAY AND TONIGHT WILL ACCELERATE MELTING
OF RECENT HEAVY SNOWS...CREATING A SIGNIFICANT FLOODING RISK ACROSS
PORTIONS OF WESTERN NEW YORK. A STRONG COLD FRONT WILL CROSS THE
REGION THIS EVENING...BRINGING A RETURN OF MORE WINTER-LIKE
TEMPERATURES AND A CHANCE OF SNOW BY LATER IN THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
THE BULK OF THE WARM FRONTAL PRECIPITATION THAT IMPACTED WESTERN
AND NORTH-CENTRAL NEW YORK OVERNIGHT IS IN THE PROCESS OF EXITING
THE NORTH COUNTRY THIS MORNING. AS EXPECTED...DOWNSLOPING
SOUTH-SOUTHEAST WINDS HELPED DIMINISH THE AMOUNT OF PRECIPITATION
THAT ACCOMPANIED THE FRONT ACROSS FAR WESTERN NEW YORK. OVERNIGHT
AMOUNTS ACROSS THE AREAS AFFECTED BY LAST WEEK`S SNOWSTORM ONLY
ENDED UP RUNNING AROUND A TENTH OF AN INCH OR LESS. WHILE THESE
LIGHTER PRECIP TOTALS SHOULD NOT SIGNIFICANTLY EXACERBATE THE CURRENT
FLOOD RISK ACROSS BUFFALO AREA CREEKS...THE CURRENT FLOOD RISK
REMAINS SIGNIFICANT GIVEN THE ABUNDANT SNOWPACK REMAINING ACROSS THE
AREA...PARTICULARLY AS THE EXPECTED WARMUP HAS BEGUN IN EARNEST WITH
AREA TEMPERATURES ALREADY WELL INTO THE 50S. CURRENT MELTING OF THE
SNOWPACK WILL ONLY ACCELERATE FROM THIS POINT ON AS DEWPOINTS HAVE
ALSO SHOT UP TOWARDS THE 50 DEGREE MARK AND WINDS ARE ALREADY
STARTING TO PICK UP ACROSS THE AREA. AREA STREAM GAGES ARE
REFLECTING THE RAPIDLY INCREASING RUNOFF AND LEVELS ARE STARTING TO
RISE QUICKLY ON AREA CREEKS AND STREAMS. ALL FLOOD WARNINGS REMAIN
IN EFFECT AS LEVELS ARE STILL EXPECTED TO RISE ABOVE FLOOD STAGE. IN
ADDITION...SNOW CLOGGED DRAINS AND SATURATED SOIL WILL CAUSE
LOCALIZED FLOODING OF LOW-LYING AREAS AS WELL AS BASEMENTS.

IN ADDITION TO THE FLOODING RISK ACROSS WESTERN NEW YORK...STRONG
WINDS WILL AFFECT MUCH OF THE FORECAST AREA TODAY AND TONIGHT AS A
RAPIDLY DEEPENING LOW PRESSURE SYSTEM OVER NORTHERN LOWER MICHIGAN
PASSES TO OUR NORTHWEST. THE TIGHT PRESSURE GRADIENT IS DRIVING
STRONG WINDS ALOFT WITH A 60KT 850MB JET CURRENTLY OVERHEAD WESTERN
NEW YORK. WHILE STRONG WINDS WERE MOSTLY CONFINED TO THE DOWNSLOPING
AREAS ALONG THE LAKE ERIE SHORELINE OVERNIGHT...DIURNAL MIXING WILL
BRING A GOOD PORTION OF THESE STRONG WINDS DOWN TO THE SURFACE
ACROSS THE FORECAST AREA THIS AFTERNOON...PARTICULARLY AS STRONGER
UPPER LEVEL WINDS MOVE OVERHEAD. THE PEAK WIND GUSTS WILL LIKELY BE
FOUND IN THE VICINITY OF A COLD FRONT THAT WILL BE CROSSING THE
FORECAST AREA FROM WEST TO EAST FROM LATE THIS AFTERNOON THROUGH
LATE THIS EVENING. DURING THIS PERIOD SOUTHWESTERLY GUSTS COULD
REACH 60 MPH ALONG THE LAKE ERIE CORRIDOR EXTENDING EAST TO
ROCHESTER. A HIGH WIND WARNING IS IN EFFECT FOR THESE AREAS. IN
ADDITION...A  HIGH WIND WARNING HAS BEEN ISSUED FOR JEFFERSON COUNTY
AS THAT AREA SHOULD BE CLOSE ENOUGH TO THE STRONGEST ISALLOBARIC
GRADIENT THIS EVENING AND WILL ALSO BE AT THE RECEIVING END OF AN
OPEN DOWN-LAKE FETCH OFF LAKE ONTARIO. COUNTIES FARTHER INLAND IN
THE NORTH COUNTRY AND ACROSS THE FINGER LAKES WILL ALSO SEE STRONG
WINDS...BUT WITH GUSTS TO AROUND 50 MPH...AND THESE AREAS ARE UNDER
A WIND ADVISORY. IN ADDITION TO THE USUAL HAZARDS POSED BY STRONG
WINDS...THESE WINDS WILL POSE AN ADDITIONAL THREAT TO THE HEAVY SNOW
AREAS GIVEN THE SATURATED SOILS AS SHALLOW ROOTED TREES WILL BE MORE
PRONE TO POTENTIALLY FALLING AND CAUSING POWER OUTAGES...HINDERING
SUMP PUMPS AND ENHANCING THE RISK FOR BASEMENT FLOODING.

AS THE STRONG WINDS VEER SOUTHWESTERLY BEHIND THE PASSING COLD
FRONT...GALES PUSHING DOWN LAKE ERIE WILL HAVE THE POTENTIAL TO
RAISE WATER LEVELS ON THE EAST END OF LAKE ERIE TOWARDS FLOOD
STAGE...AND A LAKESHORE FLOOD WATCH REMAINS IN EFFECT.

REGARDING EXPECTED PRECIPITATION...WHILE THE BULK OF THE WARM
FRONTAL PRECIPITATION HAS EXITED THE AREA...ANOTHER ROUND OF
SCATTERED LIGHT SHOWERS WILL BRUSH WESTERN NEW YORK THIS MORNING AS
A SURFACE TROUGH CROSSES THE AREA...HOWEVER ADDITIONAL RAINFALL WITH
THESE SHOWERS SHOULD BE NEGLIGIBLE. MORE WIDESPREAD SHOWER ACTIVITY
WILL OCCUR WITH THE COLD FRONTAL PASSAGE FROM LATE THIS AFTERNOON
THROUGH TONIGHT WITH AREAS PICKING UP AROUND A TENTH OF AN INCH OR
SO OF RAINFALL. THE FAST MOVING NATURE OF THE FRONT WILL HELP
MITIGATE THE AMOUNT OF RAIN ALREADY SATURATED AREAS WILL BE
RECEIVING. BEHIND THE FRONT...COLD ADVECTION MAY START TO DRIVE SOME
VERY LIGHT LAKE ENHANCED PRECIPITATION TOWARDS DAYBREAK...HOWEVER
VERY SHALLOW MOISTURE ALOFT AND MARGINALLY COLD TEMPERATURES SHOULD
KEEP ANY PRECIPITATION IN THE FORM OF SPRINKLES/FLURRIES AS
TEMPERATURES DROP TOWARDS THE FREEZING MARK.

THE STRONG WARM ADVECTION TAKING PLACE ALONG WITH THE STRONG
DOWNSLOPING EFFECT OF THE SOUTHERLY WINDS WILL PUSH TEMPERATURES
TOWARDS THE 60 DEGREE MARK ACROSS FAR WESTERN NEW YORK...HOWEVER THE
WARMEST AREAS WILL ACTUALLY BE FOUND ACROSS THE GENESEE VALLEY AND
FINGER LAKES WHERE READINGS WILL CLIMB INTO THE LOW TO MID 60S
THANKS TO DOWNSLOPING. TEMPERATURES WILL REMAIN VERY WARM INTO THE
EVENING HOURS BEFORE TAKING A SHARP DOWNWARD TURN TONIGHT AS THE
COLD FRONT MOVES THROUGH WITH READINGS DROPPING INTO THE LOW TO MID
30S ACROSS WESTERN NEW YORK WITH UPPER 30S TO LOWER 40S EAST OF THE
GENESEE VALLEY.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
A RETURN TO BELOW NORMAL TEMPERATURES IS EXPECTED THROUGH THE
REMAINDER OF THE WEEK AS THE JET STREAM BUCKLES WITH SURFACE AND
UPPER LEVEL TROUGHINESS SETTLING OVER THE GREAT LAKES. THE AIRMASS
WILL NOT BE AS COLD AS LAST WEEK BUT 850MB TEMPS FALLING TO
BETWEEN -6C AND -8C WILL KEEP SURFACE TEMPERATURES 5-10F BELOW
NORMAL OR ABOUT 20 DEGREES COOLER THAN WHAT WE WILL SEE TODAY.
TUESDAYS TEMPERATURE CURVE WILL BE NON-DIURNAL AS COLD AIR
ADVECTION KEEPS TEMPERATURES FALLING THROUGH THE 30S DURING THE
DAY BOTTOMING OUT IN THE IN THE UPPER 20S TO LOWER 30S OVERNIGHT.
TEMPS WEDNESDAY AND WEDNESDAY WILL TOP OUT IN THE LOW TO MID 30S
AND BOTTOM OUT IN THE MID TO UPPER 20S. A LINGERING PRESSURE
GRADIENT ACROSS THE LOWER LAKES WILL KEEP GUSTY SUB-ADVISORY WINDS
IN PLACE THROUGH THE BULK OF TUESDAY FINALLY TAPERING OFF TUESDAY
NIGHT.

THE PRECIPITATION FORECAST IS A BIT TRICKY THROUGH MIDWEEK. AS
MENTIONED ABOVE...THE 850MB TEMPS ARE FORECAST TO FALL TO BETWEEN
-6C AND -8C WHICH WITH LAKE WATER TEMPERATURES OF 4C ON LAKE ERIE
AND 7C ON LAKE ONTARIO IS ONLY BORDERLINE COLD ENOUGH TO SUPPORT
TRUE LAKE EFFECT. THESE MAY HOWEVER BE JUST COOL ENOUGH FOR SOME
WEAK LAKE ENHANCED PRECIPITATION. BUFKIT PROFILES SHOW LAKE INDUCED
EQUILIBRIUM LEVELS WILL ONLY RISE TO 5-6KFT ON LAKE ERIE AND 6-8KFT
ON LAKE ONTARIO. MOISTURE WILL ONLY BE LIMITED TO 5KFT AND LOWER
WITH THE DENDRITIC SNOW CRYSTAL ZONE DISPLACED ABOVE THE MOISTURE.
WITH INSTABILITY AND FORCING LIMITED TO OVER AND DOWNWIND OF THE
LAKES AND PROFILES ARE MORE FAVORABLE FOR DRIZZLE THAN SNOW HAVE
OPTED TO FORECAST A CHANCE OF LAKE ENHANCED LIGHT SNOW OR DRIZZLE
TUESDAY AND TUESDAY NIGHT WITH CHANCES LIGHT SNOW OR FREEZING
DRIZZLE RESERVED FOR WHEN TEMPS FALL BELOW FREEZING. THE LIMITED
MOISTURE SHOULD LEAVE LITTLE IF ANY ACCUMULATION OF SNOW OR DRIZZLE
WITHIN THE SHIFTING BANDS.

FOCUS THEN TURNS TOWARD A DEVELOPING NOR`EASTER LIFTING ALONG THE
EAST COAST WEDNESDAY AND WEDNESDAY NIGHT. THE 00Z ECMWF IS FURTHEST
WEST WITH THE 00Z GFS AND GEM ABOUT 150 MILES FURTHER EAST. SUCH A
DIFFERENCE IN THE TRACK STILL LEAVES MUCH UNCERTAINTY TO WHETHER OR
NOT WESTERN AND CENTRAL NEW YORK WILL SEE ANY SNOWFALL. HAVE GONE
WITH A CHANCE OF SNOW FROM ROCHESTER EAST AND SLIGHT CHANCE TO THE
WEST WHICH COVERS THE POSSIBILITY THAT THE ECMWF VERIFIES WITH A
MORE WEST TRACK. EITHER WAY THE LARGEST IMPACTS WILL BE EAST OF OUR
FORECAST AREA WITH JUST LIGHT ACCUMULATIONS POSSIBLE ACROSS CENTRAL
NEW YORK.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
IN THE WAKE OF THE DEPARTING COASTAL SYSTEM...A FRESH SHOT OF MUCH
COLDER AIR WILL OVERSPREAD THE LOWER LAKES REGION THROUGH THE END OF
THE WEEK. 850MB TEMPS FALLING TO BETWEEN -10C AND -15C ALONG WITH
LINGERING SYNOPTIC-SCALE MOISTURE WILL BE MUCH MORE FAVORABLE FOR
SOME LAKE EFFECT SNOW BUT A PASSING SURFACE TROUGH MAY ALSO BRING A
CHANCE FOR SOME AREAWIDE LIGHT SNOW. AT THIS POINT...IT APPEARS THAT
THE LARGE-SCALE FLOW WILL LARGELY BE WESTERLY OR PERHAPS EVEN A BIT
WEST-NORTHWESTERLY IN NATURE...WHICH WOULD FAVOR THE MORE
TRADITIONAL SNOW BELTS EAST AND EAST-SOUTHEAST OF THE LAKES.

ON FRIDAY INTO FRIDAY NIGHT...BUILDING SURFACE-BASED RIDGING SHOULD FORCE
ANY LAKE EFFECT SNOW/SNOW SHOWERS TO DRAMATICALLY WEAKEN AND LIFT
NORTHWARD AS THE STEERING WINDS BACK AGAIN...WITH AREAS OUTSIDE OF
ANY LAKE INFLUENCES LIKELY TO REMAIN DRY. AFTER THAT...GUIDANCE
PACKAGES ARE SUGGESTING A STRONG LOW LIFTING ACROSS THE GREAT LAKES
TO OUR WEST WITH A COLD FRONT/TROUGH PASSING ACROSS THE LOWER GREAT
LAKES. HAVE GONE WITH JUST BROAD BRUSH LOW CHANCES FOR SNOW FOR NOW.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
LLWS ACROSS THE FORECAST AREA HAS LARGELY DIMINISHED THIS MORNING AS
STRONG WINDS ALOFT ARE BEGINNING TO MIX DOWN TO THE SURFACE. EXPECT
WIDESPREAD SSW GUSTS OF 35KT TO INCREASE TO 40-50KT THIS AFTERNOON
AS STRONGER WINDS ALOFT MIX DOWN. THE STRONGEST GUSTS WILL OCCUR
INVOF A COLD FRONT EXPECTED TO CROSS THE FORECAST AREA FROM W-E
BETWEEN 23Z MON AND 04Z TUE. RAIN SHOWERS WILL ACCOMPANY THE FRONTAL
PASSAGE...HOWEVER THEY SHOULD REMAIN LIGHT ENOUGH AS NOT TO CAUSE
REDUCTIONS IN VISIBILITY BELOW VFR. EXPECT A SUBTLE WIND SHIFT TO
THE SW BEHIND THIS FRONT WITH CONTINUED STRONG GUSTS OF 40-50KT
THROUGH THE END OF THE FORECAST PERIOD. OTHERWISE...EXPECT VFR
CONDITIONS THROUGHOUT THE DAYLIGHT HOURS WITH SOME DETERIORATION TO
MVFR CIGS ACROSS UPSLOPE AREAS BEHIND THE COLD FRONT MON NIGHT.

OUTLOOK...
TUESDAY...MVFR WITH A CHANCE OF DRIZZLE/FREEZING DRIZZLE EAST OF THE
LAKES.
WEDNESDAY...MAINLY VFR WITH A CHANCE OF LAKE EFFECT SHOW SHOWERS
EAST OF THE LAKES.
THURSDAY THROUGH SATURDAY...MAINLY VFR WITH A CHANCE OF SNOW SHOWERS.

&&

.MARINE...
A RAPIDLY DEEPENING LOW PRESSURE SYSTEM WILL BE TRACKING FROM
NORTHERN LOWER MICHIGAN SOUTH OF JAMES BAY AND INTO NORTHERN QUEBEC
TONIGHT. STRONG WIND FIELDS ASSOCIATED WITH THIS LOW WILL BRING
SOUTHWESTERLY GALES TO THE LAKES LATER TODAY AND INTO
TONIGHT...PARTICULARLY AS A STRONG COLD FRONT SWEEPS ACROSS THE
LAKES.

GALES WILL SUBSIDE LATER ON TUESDAY AS THE LOW PRESSURE SYSTEM
RESPONSIBLE TRACKS OFF TO THE NORTHEAST ACROSS LABRADOR. A WEAK
AREA OF HIGH PRESSURE IS THEN EXPECTED TO SKIRT THE LAKES WITH
LIGHTER WINDS EXPECTED FOR THE MIDDLE PORTION OF THE WEEK.
WESTERLIES WILL FRESHEN ON THE LAKES TOWARDS THE END OF THE WEEK IN
THE WAKE OF A STRONG COASTAL STORM PASSING WELL TO OUR EAST ALONG
THE EASTERN SEABOARD.

&&

.HYDROLOGY...
A SNOW SURVEY COMPLETED ON FRIDAY CAME UP WITH A GENERAL 4 TO 6
INCHES OF SNOW WATER EQUIVALENT IN THE HARDEST HIT LAKE EFFECT
SNOW AREAS.

TEMPERATURES WILL RISE INTO THE 60S TODAY. DEW POINTS ACROSS THE
REGION ARE RUNNING IN THE UPPER 40S AND WILL CONTINUE TO STEADILY
RISE TO THE LOWER 50S. THE HIGHER DEWPOINTS COMBINED WITH STRONG
WINDS WILL BE VERY EFFICIENT AT RAPIDLY MELTING THE DEEP SNOW
PACK. THIS WILL RESULT IN SIGNIFICANT RISES ON LOCAL TRIBUTARIES
WITH AREAL FLOODING EXPECTED FOR THE AREAS IN FAR WESTERN NEW YORK
THAT RECEIVED THE TWO LAKE EFFECT SNOW STORMS THIS PAST WEEK.

THE FLOOD POTENTIAL WILL BE TWO FOLD. FIRST...THERE IS A GENERAL
RISK OF URBAN FLOODING IN THE TOWNS HARDEST HIT BY THE SNOW AS
MELT WATER POOLS IN LOW LYING AND POOR DRAINAGE AREAS. EXCESSIVE
SNOW PILES AND LEAVES BENEATH THE SNOW MAY BLOCK STORM DRAINS.
FLOODING OF SOME STREETS AND RESIDENTIAL BASEMENTS COULD BEGIN
ANYTIME NOW WITH MELTING UNDER WAY....SO AN AREAL FLOOD WARNING
CONTINUES THROUGH AT LEAST THIS AFTERNOON TO ADDRESS THIS THREAT.

THERE WILL ALSO BE THE RISK FOR THE FLOODING OF THE VARIOUS
CREEKS AND TRIBUTARIES ACROSS FAR WESTERN NEW YORK. THE GREATEST
THREAT IS ON THE BUFFALO CREEKS WHICH DRAIN THE HARDEST HIT AREAS
FROM THIS WEEKS LAKE EFFECT SNOW. THIS INCLUDES
CAZENOVIA...BUFFALO... CAYUGA...AND ELLICOTT. INDIVIDUAL FLOOD
WARNINGS FOR THESE CREEKS HAVE BEEN ISSUED...AS ALL ARE NOW
FORECAST TO REACH AT LEAST MINOR FLOOD LEVELS. THERE MAY ALSO BE
SOME FLOOD RISK FOR CATTARAUGUS CREEK AND SOME OF THE SMALLER
CREEKS THAT FLOW THROUGH DUNKIRK AND SILVER CREEK.

THERE IS ALSO A FAIRLY HEAVY SNOW PACK IN THE UPPER REACHES OF THE
OATKA WATERSHED...BUT NOT AS HIGH AS THE BUFFALO CREEKS. WE WILL
CONTINUE TO MONITOR THIS BASIN FOR POSSIBLE FUTURE INCLUSION IN
A FLOOD WARNING IF WE SEE STEADY RISES. THE EASTERN LAKE ONTARIO
REGION HAD LESS SNOW... WITH TOTALS OF 2 TO 2.5 FEET ON THE TUG
HILL. THIS SNOW PACK IS NOT EXCESSIVE FOR THAT AREA...SO HAVE NOT
INCLUDED THE NORTH COUNTRY IN A FLOOD WATCH AT THIS TIME.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...HIGH WIND WARNING FROM 1 PM THIS AFTERNOON TO 4 AM EST TUESDAY
     FOR NYZ001>003-007-010>012-019-085.
     WIND ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR NYZ019-085.
     LAKESHORE FLOOD WATCH FROM 4 PM EST THIS AFTERNOON THROUGH
     LATE TUESDAY NIGHT FOR NYZ010-019-085.
     WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST TUESDAY FOR
     NYZ006-008.
     WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 4 AM EST TUESDAY FOR
     NYZ004-005-013-014-020-021.
MARINE...GALE WARNING FROM 1 PM THIS AFTERNOON TO 7 PM EST TUESDAY FOR
         LEZ020-040-041.
         SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
         LEZ040-041.
         GALE WARNING FROM 1 PM THIS AFTERNOON TO 7 PM EST
         TUESDAY FOR LOZ030-042-062.
         GALE WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST TUESDAY
         FOR LOZ043>045-063>065.
         SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 7 AM
         EST TUESDAY FOR SLZ022-024.

&&

$$

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






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