Extended Streamflow Guidance
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WINTER/SPRING FLOOD POTENTIAL OUTLOOK NATIONAL WEATHER SERVICE
NORTHEAST RIVER FORECAST CENTER...TAUNTON MA
847 AM EST THU MAR 5 2015

...FOR OFFICIAL NATIONAL WEATHER SERVICE USE ONLY...

WINTER/SPRING FLOOD POTENTIAL FOR THE NORTHEASTERN U.S. /5/

THE WINTER/SPRING FLOOD POTENTIAL FOR THE NORTHEAST UNITED STATES IS
ABOVE NORMAL ACROSS MUCH OF SOUTHERN AND EASTERN NEW ENGLAND AND
MUCH OF WESTERN AND PORTIONS OF CENTRAL NEW YORK STATE. ELSEWHERE
ACROSS NEW ENGLAND AND NEW YORK STATE...THE WINTER/SPRING FLOOD
POTENTIAL IS NEAR NORMAL EXCEPT LOCALLY BELOW NORMAL ACROSS
NORTHEAST MAINE AND THE NORTHERN ADIRONDACK MOUNTAIN RANGE IN NEW
YORK STATE.

THE POTENTIAL FOR FLOODING DUE TO ICE JAMS IS SLIGHTLY ABOVE NORMAL
FOR JUST ABOUT ALL OF NEW ENGLAND AND NEW YORK STATE.

...CLIMATE GUIDANCE...

THE SEVEN STATE REGION OF NEW ENGLAND AND NEW YORK STATE IS COMING
OUT OF AN INCREDIBLY COLD MONTH AS CONSTANT ARCTIC INTRUSIONS KEPT
AN ALMOST NON-STOP SUPPLY OF BITTER COLD AIR FUNNELING INTO THE
REGION DURING FEBRUARY. MOST LONG TERM CLIMATE STATIONS REPORTED
MEAN FEBRUARY TEMPERATURES OF 10 TO 15 DEGREES BELOW NORMAL WITH
SYRACUSE NEW YORK A WHOPPING 16.9 DEGREES BELOW NORMAL FOR THE
MONTH. ALL-TIME COLDEST MONTH EVER RECORDS WERE SET AT
BUFFALO...SYRACUSE AND ROCHESTER NEW YORK AS WELL AS FOR BANGOR
MAINE. ALL-TIME COLDEST FEBRUARY RECORDS WERE SET AT BINGHAMTON NEW
YORK...HARTFORD CONNECTICUT...WORCESTER MASSACHUSETTS AND CARIBOU
MAINE. BOSTON MASSACHUSETTS HAD ITS 2ND COLDEST FEBRUARY EVER WITH
RECORDS DATING BACK TO 1872.

THERE ARE FINALLY SIGNS OF CHANGE ON THE HORIZON. MEDIUM RANGE
NUMERICAL WEATHER MODEL GUIDANCE IS SHOWING THE TENDENCY FOR THE
POLAR BRANCH OF THE JET STREAM TO RETREAT NORTHWARD TO ALONG THE
UNITED STATES BORDER WITH CANADA BY THE MIDDLE OF THE MONTH WHICH
SHOULD ALLOW FOR TEMPERATURES TO WARM UP UNDER THE HIGHER MARCH SUN
ANGLE.

CLIMATE TELECONNECTION PATTERNS SHOW THE NORTH ATLANTIC OSCILLATION
( NAO ) INDEX REMAINING PREDOMINANTLY POSITIVE AND THE PACIFIC NORTH
AMERICA ( PNA ) PATTERN GOING NEGATIVE INTO THE MIDDLE OF MARCH.
WITH THIS TYPE OF PATTERN...UPPER LEVEL RIDGING IS EXPECTED ACROSS
THE SOUTHEASTERN UNITED STATES AND A GENERAL WEST-SOUTHWEST OR
SOUTHWEST UPPER FLOW SHOULD DEVELOP WHICH WOULD PUSH THE COLDEST AIR
BACK TOWARDS THE UNITED STATES/CANADA BORDER. SO...WE ARE FAIRLY
CONFIDENT OF MODERATING TEMPERATURES OVER THE NEXT 2 WEEKS WHICH
SHOULD BEGIN TO MELT SOME OF THE DEEP SNOW CURRENTLY IN PLACE.

THE OFFICIAL NATIONAL WEATHER SERVICE 8-14 DAY OUTLOOK FOR 11-17
MARCH 2015 SEEMS TO AGREE WITH THIS GENERAL ASSESSMENT AS IT CALLS
FOR TEMPERATURES TO AVERAGE NEAR TO ABOVE NORMAL ACROSS MOST OF THE
REGION EXCEPT PERHAPS A TAD BELOW NORMAL ACROSS SOUTHERN NEW ENGLAND
AND SOUTHEAST NEW YORK STATE WHICH MAY BE A REFLECTION OF THE DEEP
SNOWPACK AND COLD OCEAN TEMPERATURES KEEPING IT LOCALLY COLDER.
PRECIPITATION FOR THE SAME TIME PERIOD IS EXPECTED TO AVERAGE BELOW
NORMAL ACROSS JUST ABOUT ALL OF NEW YORK STATE AND NEW ENGLAND.

...OBSERVED SNOW DEPTHS AND WATER EQUIVALENTS...

SNOW CONTINUES TO BLANKET 100 PERCENT OF THE NERFC SERVICE AREA AS
OF THIS MORNING WHICH IS A BIT UNUSUAL FOR EARLY MARCH. IN
FACT...MOST PLACES HAVE SEEN SNOW DEPTHS AND WATER EQUIVALENTS GO UP
OVER THE PAST TWO WEEKS.

...NEW YORK STATE...

A 1 TO 2.5 FOOT SNOWPACK COVERS THE MAJORITY OF NEW YORK STATE WITH
JUST A FEW EXCEPTIONS. SNOW DEPTHS ACROSS LONG ISLAND AND NEW YORK
CITY HAVE DROPPED TO NEAR OR LESS THAN 1 FOOT NOW AND IN THE
CHAMPLAIN VALLEY OF FAR NORTHEAST NEW YORK STATE...SNOW DEPTHS ARE
ALSO RUNNING NEAR OR UNDER 1 FOOT. OTHERWISE...DEEPER SNOW DEPTHS
ARE FOUND ACROSS THE HIGH TERRAIN SOUTH OF BUFFALO WHERE DEPTHS ARE
2 TO 3 FEET AND FROM THE TUG HILL PLATEAU AND UPPER MOHAWK RIVER
VALLEY EAST OF LAKE ONTARIO INTO THE HIGH TERRAIN OF THE ADIRONDACK
MOUNTAINS WHERE SNOW DEPTHS AVERAGE BETWEEN 2 AND 4 FEET. SNOW
DEPTHS ARE ABOVE NORMAL ACROSS MOST OF NEW YORK STATE EXCEPT FOR THE
ADIRONDACK MOUNTAIN AND LAKE CHAMPLAIN VALLEY REGIONS OF NORTHERN
NEW YORK STATE WHERE THEY ARE CLOSE TO EARLY MARCH NORMALS. SNOW
DEPTHS ARE ALSO CLOSE TO NORMAL ACROSS THE CATSKILL MOUNTAIN RANGE
IN SOUTHEAST NEW YORK STATE.

SNOW WATER EQUIVALENTS FROM NEW YORK CITY EAST ACROSS LONG ISLAND
AVERAGE BETWEEN 1 AND 3 INCHES. ELSEWHERE IN NEW YORK STATE...MOST
LOWER ELEVATIONS ARE REPORTING BETWEEN 3 AND 6 INCHES OF WATER HELD
IN THE SNOWPACK WITH HIGHER AMOUNTS IN SOME SPOTS. FOR
INSTANCE...THE HIGH TERRAIN SOUTH OF BUFFALO IS REPORTING SNOW WATER
EQUIVALENTS UP TO 7 INCHES AND FROM THE TUG HILL PLATEAU EAST AND
NORTHEAST ACROSS THE UPPER MOHAWK AND ADIRONDACK MOUNTAIN REGIONS IN
NORTHERN NEW YORK STATE...SNOW WATER EQUIVALENTS AVERAGE BETWEEN 4
AND 8 INCHES BUT DO EXCEED 10 INCHES IN SPOTS ABOVE 2000 FEET. SNOW
WATER EQUIVALENTS ARE ABOVE NORMAL ACROSS A LOT OF WESTERN AND
SOUTHEASTERN NEW YORK STATE INCLUDING LONG ISLAND AND NEW YORK CITY
BUT NOT TOO FAR FROM NORMAL ELSEWHERE FOR EARLY MARCH. IN FACT...FOR
WESTERN NEW YORK STATE...SNOW WATER EQUIVALENTS ARE CURRENTLY
RUNNING 200 TO 300 PERCENT OF NORMAL.

...SOUTHERN NEW ENGLAND...

SNOW DEPTHS OF 1.5 TO 3 FEET ARE VERY COMMON ACROSS SOUTHERN NEW
ENGLAND RIGHT TO THE COAST. THE ONLY SPOTS WITH LESS SNOW ARE FOUND
ACROSS OUTER CAPE COD AND THE ISLANDS IN SOUTHEAST MASSACHUSETTS
WHERE SNOW DEPTHS HAVE DROPPED TO NEAR OR LESS THAN 1 FOOT NOW. THE
BLUE HILL OBSERVATORY AT AN ELEVATION OF ABOUT 635 FEET ABOUT 12
MILES SOUTHWEST OF BOSTON REPORTED 37 INCHES OF SNOW ON THE GROUND
AS OF WEDNESDAY MORNING. SNOW DEPTHS ARE MUCH ABOVE NORMAL NEAR THE
COAST IN SOUTHERN NEW ENGLAND FOR EARLY MARCH BUT CLOSER TO NORMAL
ACROSS WESTERN MASSACHUSETTS AND WESTERN CONNECTICUT.

4 TO 9 INCH SNOW WATER EQUIVALENTS ARE THE NORMAL ACROSS SOUTHERN
NEW ENGLAND EXCEPT RIGHT ALONG THE SOUTH COAST...OUTER CAPE COD AND
THE ISLANDS WHERE THEY AVERAGE BETWEEN 2 AND 4 INCHES. USUALLY...THE
HIGHER SNOW WATER EQUIVALENTS WOULD BE LOCATED ACROSS THE HIGH
TERRAIN OF WESTERN MASSACHUSETTS AND WESTERN CONNECTICUT BUT
CURRENTLY...THE HIGHEST SNOW WATER EQUIVALENTS ARE FOUND ACROSS EAST
COASTAL MASSACHUSETTS WHERE THEY ARE AT OR ABOVE 6 INCHES. SNOW
SURVEYS LAST WEEK FOUND 8.6 INCHES OF WATER IN THE SNOWPACK AT THE
BLUE HILL OBSERVATORY JUST OUTSIDE OF BOSTON. OTHER THAN FOR THE
BERKSHIRES OF WESTERN MASSACHUSETTS AND HILLS OF NORTHWEST
CONNECTICUT WHERE SNOW WATER EQUIVALENTS ARE NEAR NORMAL FOR EARLY
MARCH...SNOW WATER EQUIVALENTS ARE ABOVE TO MUCH ABOVE NORMAL OVER
SOUTHERN NEW ENGLAND.

...VERMONT AND NEW HAMPSHIRE...

ACROSS VERMONT AND NEW HAMPSHIRE...SNOW DEPTHS ARE FAIRLY UNIFORM
BETWEEN 1.5 AND 3 FEET WITH HIGHER AMOUNTS APPROACHING OR EXCEEDING
4 FEET CONFINED TO THE HIGHER ELEVATIONS OF THE GREEN MOUNTAINS IN
VERMONT AND WHITE MOUNTAINS IN NEW HAMPSHIRE...MOSTLY ABOVE 2000
FEET. FOR INSTANCE...ON MOUNT MANSFIELD IN NORTHERN VERMONT...A SNOW
DEPTH OF 62 INCHES WAS MEASURED TUESDAY 3 MARCH AT AN ELEVATION OF
3000 FEET. THE ONLY SPOTS WHERE SNOW DEPTHS ARE RUNNING BELOW A FOOT
ARE FOUND ACROSS THE CHAMPLAIN VALLEY IN NORTHWEST VERMONT WHERE
BURLINGTON REPORTED A SNOW DEPTH OF JUST 8 INCHES YESTERDAY MORNING.
SNOW DEPTHS ARE ABOVE NORMAL ACROSS A LOT OF SOUTHERN NEW HAMPSHIRE
BUT CLOSER TO NORMAL ACROSS THE REMAINDER OF NEW HAMPSHIRE AND
VERMONT FOR LATE WINTER.

ACROSS BOTH NEW HAMPSHIRE AND VERMONT...SNOW WATER EQUIVALENTS OF 4
TO 8 INCHES ARE THE NORM WITH HIGHER AMOUNTS TO NEAR AND OVER 10
INCHES FOUND ABOVE 2000 FEET IN THE GREEN MOUNTAINS OF VERMONT AND
WHITE MOUNTAINS OF NORTHERN NEW HAMPSHIRE. AGAIN...ABNORMALLY HIGH
SNOW WATER EQUIVALENTS ARE FOUND RIGHT TO THE COAST IN SOUTHEAST NEW
HAMPSHIRE WHERE WATER EQUIVALENTS ARE CLOSE TO 8 INCHES. LOWER SNOW
WATER EQUIVALENTS OF 1 TO 3 INCHES ARE BEING REPORTED ACROSS THE
CHAMPLAIN VALLEY IN NORTHWEST VERMONT WHICH IS NOT UNUSUAL FOR EARLY
MARCH. SNOW WATER EQUIVALENTS CONTINUE ABOVE TO MUCH ABOVE NORMAL
ACROSS SOUTHERN AND ESPECIALLY SOUTHEASTERN NEW HAMPSHIRE BUT
OTHERWISE ARE FAIRLY CLOSE TO NORMAL ACROSS BOTH STATES FOR EARLY
MARCH.

...MAINE...

ACROSS MAINE...WIDESPREAD SNOW DEPTHS OF 2 TO 4 FEET ARE FOUND WITH
AMOUNTS CLOSE TO 5 FEET ACROSS COASTAL DOWNEAST MAINE.
IRONICALLY...THE FARTHER NORTH YOU TRAVEL IN MAINE THE LOWER THE
SNOW DEPTHS BECOME. SNOW DEPTHS ACROSS FAR NORTHEAST MAINE ARE
RUNNING ONLY BETWEEN 1 AND 2 FEET. THE JACKPOT FOR SNOW RIGHT NOW
COMES FROM THE DOWNEAST COAST WHERE MACHIAS REPORTED 60 INCHES ON
THE GROUND YESTERDAY MORNING. SNOW DEPTHS ACROSS MAINE ARE ABOVE TO
MUCH ABOVE NORMAL ALONG THE COAST TRANSITIONING TO NEAR OR EVEN A
TAD BELOW NORMAL ACROSS FAR NORTHERN MAINE.

SNOW WATER EQUIVALENTS ACROSS MOST OF MAINE AVERAGE BETWEEN 5 AND 10
INCHES WITH THE HIGHER VALUES NEAR THE COAST AND LOWEST VALUES IN
THE MOUNTAINS. AMOUNTS ARE EVEN HIGHER ACROSS COASTAL DOWNEAST MAINE
WHERE SNOW WATER EQUIVALENTS AVERAGE BETWEEN 8 AND 12 INCHES AND ARE
LOCALLY LOWER ACROSS FAR NORTHEAST MAINE WHERE JUST 2 TO 5 INCHES OF
WATER IS LOCKED UP IN THE SNOWPACK. SNOW WATER EQUIVALENTS ARE ABOVE
TO MUCH ABOVE NORMAL ACROSS SOUTHERN MAINE ESPECIALLY NEAR THE
COAST...BUT JUST NEAR TO IN SOME INSTANCES A TAD BELOW NORMAL ACROSS
FAR NORTHERN MAINE.

...SOIL MOISTURE CONDITIONS AND WATER SUPPLY...

WITH INCREDIBLY COLD TEMPERATURES AND VERY LITTLE RUNOFF OCCURRING
SINCE ABOUT MID-JANUARY...ANTECEDENT MOISTURE STATES HAVE CONTINUED
TO DRY OUT ACROSS MOST OF NEW ENGLAND AND NEW YORK
STATE...ESPECIALLY ACROSS INTERIOR NEW YORK STATE WHERE THE COLD
EXTENDED BACK THROUGH MOST OF JANUARY AS WELL. NEAR SURFACE SOIL
MOISTURE ANOMALY MAPS FROM 2 MARCH 2015 SHOW THIS TREND QUITE
NICELY. VERY DRY CONDITIONS ARE DEPICTED ACROSS JUST ABOUT ALL OF
NORTHERN...CENTRAL AND WESTERN NEW YORK STATE. FURTHER
EAST...MOISTURE STATES ARE CLOSER TO NORMAL EXCEPT SLIGHTLY WETTER
THAN NORMAL ACROSS COASTAL MAINE WHERE A NON STOP TRAIN OF STORMS
HAS KEPT DUMPING SNOW ON THE GROUND. WE HAVE ALSO RECENTLY OBSERVED
SOME MELT ACROSS LONG ISLAND SO NEAR SURFACE MOISTURE STATES ARE
LIKELY CLIMBING THERE AS WELL.

THE LONGER TERM PALMER DROUGHT SEVERITY INDEX FROM 28 FEBRUARY 2015
WHICH MEASURES ANTECEDENT MOISTURE STATES ON A LONGER SCALE ( WEEKS
TO MONTHS ) SHOWS NEAR NORMAL MOISTURE STATES ACROSS MOST OF NEW
YORK STATE AND NORTHERN NEW ENGLAND...BUT STILL REFLECTS THE HIGH
PRECIPITATION AMOUNTS ACROSS MOST OF COASTAL EASTERN NEW ENGLAND
WHERE UNUSUALLY TO VERY MOIST CONDITIONS ARE BEING DEPICTED.

EXAMINING GROUNDWATER MONITORING WELLS ACROSS THE REGION COURTESY OF
THE UNITED STATES GEOLOGICAL SURVEY ( USGS ) SHOWS MOST AREAS HAVING
BELOW TO MUCH BELOW NORMAL GROUNDWATER LEVELS. THIS IS IN LARGE PART
DUE TO THE LACK OF RUNOFF OVER THE PAST FEW MONTHS AS MOST OF THE
SNOWPACK HAS REMAINED INTACT. THE SITUATION IS DRAMATIC IN NEW YORK
STATE WHERE MOST GROUNDWATER MONITORING WELLS WITH LESS THAN 15
YEARS OF RECORD WERE AT ALL TIME LOWS FOR MARCH GROUNDWATER LEVELS.
EVEN LONGER TERM WELLS LIKE HARTWICK IN EAST CENTRAL NEW
YORK...PLATTSBURGH IN NORTHEAST NEW YORK AND PANAMA IN SOUTHWEST NEW
YORK WHERE RECORDS GO BACK NEAR OR OVER 25 YEARS WERE AT ALL TIME
RECORD LOW LEVELS FOR MARCH. THE ONLY AREAS IN NEW YORK STATE SEEING
GROUNDWATER LEVELS NEAR NORMAL ARE FOUND ACROSS PORTIONS OF LONG
ISLAND WHERE SNOWMELT HAS BEGUN TO RECHARGE THE SYSTEM AND EAST OF
LAKE ONTARIO FROM THE TUG HILL PLATEAU INTO THE WESTERN ADIRONDACKS
WHERE GROUNDWATER LEVELS ARE CLOSE TO NORMAL. THERE IS PLENTY OF
SNOW TO RECHARGE THESE LOW GROUNDWATER LEVELS...HOWEVER...IT IS
SOMETHING WE WILL HAVE TO WATCH CLOSELY HEADING TOWARDS SPRING.

ACROSS NEW ENGLAND...GROUNDWATER LEVELS ARE MOSTLY BELOW NORMAL
ACROSS THE INTERIOR TRENDING TO NEAR NORMAL ALONG THE EAST COAST.
CONDITIONS IN NEW ENGLAND ARE GENERALLY NOT AS BAD AS NEW YORK STATE
ALTHOUGH SOME RECORD LOW LEVELS ARE ALSO BEING REPORTED. FOR
EXAMPLE...THE USGS GROUNDWATER MONITORING WELL AT RICHMOND IN
INTERIOR SOUTHWEST RHODE ISLAND WAS AT AN ALL TIME RECORD LOW MARCH
LEVEL...GOING BACK THROUGH 39 YEARS OF RECORD. THE AMOUNT OF SNOW
WATER AVAILABLE FOR RECHARGE IN NEW ENGLAND IS GENERALLY EXPECTED TO
BE PLENTIFUL SO WE ARE NOT CURRENTLY WORRIED ABOUT ANY WATER SUPPLY
PROBLEMS HEADING INTO SPRING.

MOST LAKES AND RESERVOIRS ACROSS NEW YORK STATE ARE RUNNING BELOW
NORMAL FOR EARLY MARCH. FOR EXAMPLE...INDIAN LAKE AND LAKE CHAMPLAIN
IN NORTHERN NEW YORK STATE WERE BOTH RUNNING ABOUT 1 FOOT BELOW
NORMAL LEVELS FOR MARCH 1ST WHILE THE NEW YORK CITY WATER SUPPLY
SYSTEM...COMPRISED OF 7 LARGE RESERVOIRS ACROSS SOUTHEASTERN NEW
YORK STATE...WAS AT 74.6 PERCENT CAPACITY WHICH WAS 12.6 PERCENT
BELOW NORMAL FOR 2 MARCH 2015. WITH JUST NEAR NORMAL AMOUNTS OF SNOW
IN THE CATSKILLS...THIS IS SOMETHING THAT NEEDS TO BE WATCHED GOING
INTO SPRING. IN NEW ENGLAND...WATER SUPPLY RESERVOIRS ARE GENERALLY
AT ADEQUATE LEVELS FOR LATE WINTER. ACROSS SOUTHERN NEW
ENGLAND...BOTH QUABBIN AND SCITUATE RESERVOIRS ARE AT NO RISK OF
BEING LOW COMING OUT OF WINTER AND RESERVOIR LEVELS IN THE
ANDROSCOGGIN AND KENNEBEC RIVER BASINS IN WESTERN MAINE ARE NEAR OR
ABOVE NORMAL FOR EARLY MARCH. SO...TO SUM UP...WE ARE MOST CONCERNED
FOR POTENTIAL WATER ISSUES IN NEW YORK STATE IF THE SNOWPACK RUNS
OFF TOO QUICKLY THIS SPRING SINCE RESERVOIR AND GROUNDWATER LEVELS
ARE LOW.

...RIVER AND ICE CONDITIONS...

RIVER FLOWS ACROSS NEW YORK STATE AND NEW ENGLAND ARE MOSTLY RUNNING
BELOW TO MUCH BELOW NORMAL. A LOT OF THIS IS DUE TO THE COLD WEATHER
AND LACK OF RUNOFF SINCE MID-JANUARY RATHER THAN DUE TO A LACK OF
PRECIPITATION. FOR INSTANCE...THE WOOD RIVER AT HOPE VALLEY RHODE
ISLAND WAS FLOWING AT A RECORD LOW LEVEL FOR 4 MARCH...PASSING JUST
66 CUBIC FEET PER SECOND WHICH WAS THE LOWEST FLOW IN THE 73 YEAR
PERIOD OF RECORD FOR THAT DATE. RIVER FLOWS ARE A BIT CLOSER TO
NORMAL ACROSS MAINE AND PORTIONS OF NORTHERN NEW HAMPSHIRE AND
NORTHERN VERMONT WHERE WE TYPICALLY DO NOT SEE MUCH RUNOFF THROUGH
FEBRUARY. RIVER FLOWS ARE ALSO CLOSER TO NORMAL ACROSS LONG ISLAND
IN NEW YORK STATE DUE TO RECENT RAIN AND SNOWMELT.

THE AMOUNT OF RIVER ICE STILL IN PLACE ACROSS THE NERFC SERVICE AREA
IS STAGGERING FOR EARLY MARCH. RIVER ICE COVERS JUST ABOUT ALL
RIVERS AND STREAMS ALL THE WAY TO THE COAST IN SOUTHERN NEW ENGLAND
AND SOUTHEAST NEW YORK STATE. ICE THICKNESSES NEAR THE COAST ARE
GENERALLY NEAR OR LESS THAN 6 INCHES BUT FOR MOST OF INTERIOR NEW
YORK STATE AND NEW ENGLAND AWAY FROM THE SOUTH COAST...ICE
THICKNESSES OF 1 TO 2.5 FEET ARE COMMON. THE OVER 2 FOOT ICE
THICKNESSES ARE GENERALLY CONFINED TO NORTHERN NEW YORK STATE AND
NORTHERN NEW ENGLAND. SOME ICE JAMS REMAIN IN PLACE FROM EARLIER
BREAKUP ACTIVITY THAT HAPPENED BACK AROUND CHRISTMAS. IN
MAINE...NOTABLE ICE JAMS ARE IN PLACE ALONG THE SAINT JOHN RIVER AT
ST. FRANCIS AND MADAWASKA...THE AROOSTOOK RIVER NEAR WASHBURN AND
FORT FAIRFIELD...THE PENOBSCOT RIVER NEAR ORONO/VEAZIE AND ALONG THE
PISCATAQUIS RIVER NEAR MAXFIELD.

SINCE WE ARE NOW INTO MARCH...RIVER ICE IN THE SOUTH WILL START TO
RAPIDLY DECAY DUE TO THE INCREASINGLY HIGH SUN ANGLE AND INCREASED
SOLAR RADIATION. HOWEVER...IN CENTRAL AND NORTHERN NEW YORK STATE
AND CENTRAL AND NORTHERN NEW ENGLAND...THE ICE COULD REMAIN INTACT
FOR SEVERAL MORE WEEKS.

...CONCLUSION...

BASED ON THE INFORMATION AVAILABLE AT THIS TIME...THE WINTER/SPRING
FLOOD POTENTIAL IS ABOVE NORMAL ACROSS MUCH OF SOUTHERN/EASTERN NEW
ENGLAND. IN THESE AREAS...ALTHOUGH RIVER FLOWS AND GROUNDWATER
LEVELS ARE NEAR TO BELOW NORMAL...LONG TERM ANTECEDENT MOISTURE
STATES ARE NEAR TO IN SOME INSTANCES ABOVE NORMAL AND SNOW WATER
EQUIVALENT IS ABOVE TO MUCH ABOVE NORMAL WITH MANY AREAS SEEING NEAR
OR MORE THAN 6 INCHES OF WATER HELD IN THE SNOWPACK. NOW THAT WE ARE
INTO MARCH...MELTING SNOW WILL BEGIN TO RAISE RIVER LEVELS AND THAT
WILL LEAVE THE REGION VERY VULNERABLE TO ANY MAJOR RAIN EVENTS
LIKELY RIGHT INTO APRIL. WITH SO MUCH WATER IN THE SNOWPACK...EVEN
WITH NO LARGE RUNOFF EVENTS IN SIGHT...IT IS STILL MORE LIKELY THAN
NORMAL THAT WE WILL SEE FLOODING ACROSS THESE AREAS THIS SPRING.

THE WINTER/SPRING FLOOD POTENTIAL IS ALSO ABOVE NORMAL FOR MUCH OF
WESTERN AND PORTIONS OF CENTRAL NEW YORK STATE. IN THESE
AREAS...GROUNDWATER AND RIVER LEVELS ARE WELL BELOW NORMAL AND IN
SOME CASES AT RECORD LOW LEVELS. HOWEVER...MUCH OF THIS AREA STILL
HAS 3 TO 6 INCHES OF WATER BEING HELD IN THE SNOWPACK WHICH IS MORE
THAN NORMAL FOR EARLY MARCH...IN SOME INSTANCES ABOUT 300 PERCENT OF
NORMAL. ONCE THE SNOW STARTS TO MELT...SOIL STATES SHOULD SATURATE
AGAIN LEAVING THE AREA VULNERABLE TO ANY LARGE SCALE RAIN EVENTS.
THE THREAT IS HIGHEST FOR THE SMALL STREAMS AND CREEKS IN AND AROUND
BUFFALO WHERE RUNOFF AND WARMING CAN COME QUICK BUT DOES EXTEND EAST
TO SOME OF THE SMALL STREAMS AND CREEKS AS FAR EAST AS ABOUT
SYRACUSE.

ACROSS THE REMAINDER OF THE NERFC SERVICE AREA...TO INCLUDE NORTHERN
MAINE...VERMONT...WESTERN MASSACHUSETTS...WESTERN CONNECTICUT AND
PORTIONS OF EASTERN/NORTHERN NEW YORK STATE...THE WINTER/SPRING
FLOOD POTENTIAL IS NEAR NORMAL. IN THESE AREAS...THE PRIMARY FACTOR
DETERMINING THE NEAR NORMAL FLOOD THREAT IS THE NEAR NORMAL AMOUNTS
OF SNOW WATER IN THE PACK. TAKING INTO ACCOUNT THE BELOW NORMAL
RIVER FLOWS...BELOW NORMAL GROUNDWATER LEVELS AND NEAR TO SOMEWHAT
DRY ANTECEDENT CONDITIONS...THE FLOOD THREAT HEADING INTO SPRING
SEEMS TO BE AT MOST NEAR NORMAL. IT MAY EVEN BE A TAD BELOW NORMAL
ACROSS PORTIONS OF THE NORTHERN ADIRONDACKS IN NORTHERN NEW YORK
STATE AND NORTHEAST MAINE WHERE THE SNOWPACK IS A BIT UNDERDONE FOR
EARLY MARCH.

THE POTENTIAL FOR FLOODING DUE TO ICE JAMS IS SLIGHTLY ABOVE NORMAL
ACROSS VIRTUALLY THE ENTIRE NERFC SERVICE AREA. ICE REMAINS IN
ALMOST ALL NERFC RIVERS...FROM THE COAST TO FAR NORTHERN AREAS. NEAR
THE COAST IN SOUTHERN NEW ENGLAND...SOME RIVERS ARE OPENING UP NOW
AND OVER THE NEXT 2 WEEKS WE FEEL THAT RIVER ICE WILL CONTINUE TO
ROT AND DECAY ACROSS SOUTHERN NEW ENGLAND AND SOUTHERN/WESTERN NEW
YORK STATE. HOWEVER...UNTIL WE CAN CLEAR THIS ICE...ITS THICKNESS
AND COVERAGE LEAVE THESE AREAS VULNERABLE IF IT STARTS TO MOVE DUE
TO ANY SUBSTANTIAL RUNOFF. TWO WEEKS FROM NOW...HOWEVER...WE THINK
THE THREAT WILL HAVE SUBSIDED GREATLY ACROSS MOST OF SOUTHERN NEW
ENGLAND AND FAR SOUTHEASTERN NEW YORK STATE.

ACROSS CENTRAL AND NORTHERN NEW ENGLAND AND INTERIOR NEW YORK
STATE...THE RIVER ICE IS QUITE THICK...AVERAGING BETWEEN 1 AND 2.5
FEET THICK. AND IT IS STILL HARD AND STRUCTURALLY SOUND. IT WILL
TAKE A LOT OF WORK FROM THE INCREASING SUN ANGLE TO BEGIN TO WEAKEN
THIS ICE SO WE FEEL THE ICE JAM THREAT WILL REMAIN WELL INTO MARCH
AND EASILY INTO APRIL ACROSS NORTHERN MAINE. SO...ANY LARGE SCALE
RUNOFF EVENTS OVER THE NEXT MONTH WILL HAVE THE POTENTIAL TO CAUSE
ICE JAM RELATED FLOODING...EASILY JUSTIFYING THE ABOVE NORMAL THREAT.

IT IS IMPORTANT TO REMEMBER THAT VERY HEAVY RAINFALL CAN BRING
FLOODING AT ANY TIME OF YEAR...EVEN IN AREAS THAT HAVE LITTLE OR NO
SNOW ON THE GROUND.

A GRAPHIC DEPICTING THE FLOOD POTENTIAL ON A BASIN BY BASIN BASIS IS
AVAILABLE ON THE NERFC WEB SITE AT

                  ***WWW.ERH.NOAA.GOV/NERFC/SFPOG.HTML***

ALL IN LOWER CASE.

THE NEXT WINTER/SPRING FLOOD POTENTIAL OUTLOOK WILL BE ISSUED BY THE
NERFC ON THURSDAY MARCH 12TH 2015.

END/HORWOOD
$$



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