000
FGUS71 KBUF 242055
ESFBUF
NYC003-009-011-013-029-037-045-049-051-055-063-069-073-075-117-
121-072100-

WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE BUFFALO NY
355 PM EST THU JAN 24 2013

...BELOW NORMAL FLOOD POTENTIAL THROUGH EARLY FEBRUARY...
...A SLIGHT RISK OF ICE JAMS LATE JANUARY...

THIS IS THE SECOND WINTER / SPRING FLOOD POTENTIAL OUTLOOK OF THE 2012
SEASON. FLOOD OUTLOOKS WILL BE ISSUED EVERY TWO WEEKS INTO EARLY
SPRING TO SUMMARIZE BASIN HYDROMETEOROLOGICAL CONDITIONS AND TO
ASSESS THE POTENTIAL FOR FLOODING. THE OUTLOOKS ARE BASED ON
CURRENT AND FORECAST HYDROMETEOROLOGICAL CONDITIONS. THIS INCLUDES
SNOW COVER AND SNOW WATER EQUIVALENT...CREEK AND RIVER LEVELS AND
THE AMOUNT OF ICE COVER ON THEM...ALONG WITH THE EXPECTED
PRECIPITATION OVER THE NEXT TWO WEEKS.

...CURRENT CONDITIONS SUMMARY...

JUST AS SNOW PACK BEGAN TO GET ESTABLISHED EARLY JANUARY...A SIGNIFICANT
WARM UP MELTED MUCH OF THE DEVELOPING SNOW PACK IN THE MIDDLE
PART OF THE MONTH. FOR MOST BASINS...THIS RESULTED IN A COMPLETE
MELT OF ALL SNOW AND CREEK/RIVER ICE. ONLY THE BLACK RIVER BASIN AND TUG
HILL REGIONS RETAINED A SIGNIFICANT SNOW PACK FROM SNOWS PRIOR TO
THE WARM UP. THESE LOCATIONS HAD AN ABOVE NORMAL SNOW PACK EARLY
JANUARY...BUT THE WARM UP PROVIDED SOME MELTING AND ALSO RESULTED
IN A MORE DENSE SNOW PACK.

FOLLOWING THE UNSEASONABLY WARM WEATHER...TEMPERATURES DROPPED
MUCH BELOW NORMAL FOR SEVERAL DAYS LEADING UP TO JANUARY 24TH.
THIS COLD AIR RESULTED IN SEVERAL DAYS OF LAKE SNOWS SOUTH AND
EAST OF EACH LAKE. THIS IS THE MAIN SOURCE OF SNOW PACK IN THE
BUFFALO CREEKS AND THE GENESEE AND ALLEGHENY BASINS. SNOW PACK IS
STILL QUITE FLUFFY IN THESE REGIONS...WITH BELOW NORMAL WATER EQUIVALENT
VALUES. IN THE BLACK RIVER BASIN AND TUG HILL REGIONS...ADDITIONAL LAKE
SNOWS ADDED TO SNOW PACK...BUT BECAUSE OF THE SNOW MELT FROM THE
WARM UP...WATER EQUIVALENT VALUES HAVE DROPPED TO NEAR NORMAL FOR
THIS TIME OF YEAR.

WHILE ICE ON THE CREEKS AND RIVERS IS STILL BELOW NORMAL FOR THIS
TIME OF YEAR...BITTERLY COLD TEMPERATURES HAVE RESULTED IN A
RAPIDLY EXPANDING RIVER AND CREEK ICE OVER THE PAST COUPLE DAYS.

THE FOLLOWING IS A SUMMARY OF CONDITIONS AND OUTLOOK BY BASIN AS
OF THURSDAY MORNING ON JANUARY 24TH:

...BUFFALO AREA CREEKS / LAKE ERIE BASIN...
.SNOW COVER..........2 TO 8 INCHES.
.WATER EQUIVALENT....AN INCH OR LESS.
.CREEK FLOWS.........NEAR NORMAL.
.CREEK ICE...........THIN TO MODERATE.
.GROUND FROST........6 INCHES. 
.GROUND STATE........SATURATED.

...GENESEE RIVER BASIN / FINGER LAKES / ROCHESTER AREA...
.SNOW COVER..........1 TO 4 INCHES WITH 4 TO 8 IN SOUTHERN PORTIONS.
.WATER EQUIVALENT....AN INCH OR LESS.
.RIVER/CREEK FLOWS...NEAR NORMAL.
.RIVER/CREEK ICE.....THIN TO MODERATE ON CREEKS...PATCHY ON THE RIVER.
.GROUND FROST........6 INCHES.
.GROUND STATE........SATURATED.

...ALLEGHENY RIVER BASIN...
.SNOW COVER..........4 TO 12 INCHES.
.WATER EQUIVALENT....0.5 TO 1.5 INCHES.
.RIVER/CREEK FLOWS...NEAR NORMAL.
.RIVER CREEK ICE.....MODERATE ON CREEKS...PATCHY ON THE RIVER.
.GROUND FROST........6 TO 12 INCHES.
.GROUND STATE........SATURATED.

...BLACK RIVER BASINS / TUG HILL...
.SNOW COVER..........4 TO 12 INCHES...12 TO 24 INCHES ON TUG HILL.
.WATER EQUIVALENT....1 TO 2 INCHES...2 TO 5 INCHES TUG HILL.
.RIVER/CREEK FLOWS...NEAR NORMAL.
.RIVER/CREEK ICE.....THICK ON CREEKS...THIN TO MODERATE ON RIVER.
.GROUND FROST........12 TO 18 INCHES.
.GROUND STATE........SATURATED.

...TEMPERATURE AND PRECIPITATION OUTLOOK...

TEMPERATURES WILL START OFF MUCH BELOW NORMAL...WITH A VERY SMALL
CHANCE FOR FLOODING THROUGH EARLY NEXT WEEK. LIGHT LAKE SNOWS AND
A WEAK LOW PRESSURE SYSTEM MAY ADD VERY MODEST WATER EQUIVALENT
AMOUNTS BY EARLY NEXT WEEK...LIKELY TO HAVE LITTLE IMPACT ON FLOOD POTENTIAL.

MODEL GUIDANCE IS CONSISTENT IN FORECASTING A BRIEF WARM UP DURING
THE MIDDLE PORTION OF NEXT WEEK ON JANUARY 29TH AND 30TH. SOME
RAIN WILL LIKELY ACCOMPANY THIS WARM UP...HOWEVER MOST MODEL
GUIDANCE SUGGESTS RELATIVELY LIGHT AMOUNTS.

AFTER THIS...AND INTO THE FIRST WEEK OF FEBRUARY...IT IS LIKELY
THAT COLD AIR WILL ONCE AGAIN BUILD INTO THE REGION. THE 8 TO 14
DAY FORECAST CALLS FOR BELOW NORMAL TEMPERATURES...WITH ANY
PRECIPITATION THAT DOES FALL LIKELY TO BE SNOW.

...FLOOD POTENTIAL OUTLOOK...

IT APPEARS THE ONLY REASONABLE CHANCE FOR FLOODING WILL BE LATE
JANUARY WHEN A BRIEF WARM UP IS FORECAST. WARMER TEMPERATURES MAY
BE ENOUGH TO MELT THE LIGHT SNOW PACK...BUT PROBABLY WILL NOT BE
ENOUGH TO CAUSE ANY RUN OFF IN THE BLACK RIVER BASIN. EVEN WHERE
SNOW DOES MELT...MODEL GUIDANCE SUGGESTS THAT RAINFALL WILL
PROBABLY ON THE LIGHT SIDE...AND NOT ENOUGH TO CAUSE RIVER
FLOODING EVEN WHEN COMBINED WITH SNOW MELT. MMEFS ENSEMBLE DATA
SHOWS THERE IS A VERY SMALL CHANCE FOR RIVER FLOODING.

THERE STILL IS ONE POSSIBILITY TO WATCH FOR AS ICE ON THE CREEKS
THICKENS IN THE COLD WEATHER. BY LATE JANUARY...CREEK ICE WILL
PROBABLY BE JUST THICK ENOUGH TO RESULT IN ICE JAMS IF A BREAK UP
WERE TO OCCUR. BECAUSE OF THE TIMEFRAME...AND RELATIVELY BRIEF
PERIOD OF WARM TEMPERATURES...A BREAK UP OF CREEK ICE IS QUITE
UNCERTAIN. IF FORECASTS TREND TOWARD A WARMER AND WETTER SOLUTION
THAN IS CURRENTLY EXPECTED...THEN ICE JAMS ARE POSSIBLE IN THE
TYPICALLY VULNERABLE LOCATIONS ON SOME OF THE BUFFALO CREEKS.

OTHERWISE...COLDER TEMPERATURES ARE FORECAST TO RETURN FOR THE
FIRST WEEK OF FEBRUARY. WITH WELL BELOW FREEZING TEMPERATURES
LIKELY...THE CHANCE FOR ANY RAIN OR SNOW MELT WILL BE MINIMAL.
WHEN TAKING THESE FACTORS INTO CONSIDERATION...SEE THE OVERALL
FLOOD POTENTIAL TO BE BELOW NORMAL THROUGH EARLY FEBRUARY. THE
BEST CHANCE FOR ANY FLOODING ISSUES WILL COME FROM A SLIGHT RISK
OF ICE JAMS ASSOCIATED WITH A BRIEF LATE JANUARY WARM UP.

...ADDITIONAL INFORMATION...

REAL TIME RIVER INFORMATION AND PROBABILISTIC FORECASTS FOR
SPECIFIC LOCATIONS ALONG RIVERS ACROSS WESTERN NEW YORK CAN BE
FOUND ON THE INTERNET AT WWW.WEATHER.GOV/BUF BY CLICKING ON THE
RIVERS AND LAKES AHPS LINK ON THE LEFT SIDE OF THE PAGE. SINCE
CONDITIONS CAN CHANGE PLEASE REFER TO THE LATEST FLOOD
WARNINGS...WATCHES...AND STATEMENTS FOR ADDITIONAL INFORMATION.

THE NEXT REGULARLY SCHEDULED OUTLOOK WILL BE ISSUED BY THURSDAY
FEBRUARY 7TH. THANKS TO ALL THE OBSERVERS AND AGENCIES WHICH HAVE
HELPED GATHER DATA IN SUPPORT OF THIS OUTLOOK.

$$

APFFEL