Extended Streamflow Guidance
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WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE
NORTHEAST RIVER FORECAST CENTER...TAUNTON MA
1001 AM EDT THU APR 17 2014

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

WINTER/SPRING FLOOD POTENTIAL FOR THE NORTHEASTERN U.S. /8/

THE SPRING FLOOD POTENTIAL FOR THE NORTHEASTERN UNITED STATES IS
NEAR NORMAL ACROSS WESTERN NEW YORK...EXTREME SOUTHEASTERN NEW YORK
STATE INCLUDING THE LOWER HUDSON VALLEY AND MOST OF SOUTHERN NEW
ENGLAND EXCEPT THE LOWER CONNECTICUT RIVER BASIN.

THE SPRING FLOOD POTENTIAL REMAINS ABOVE NORMAL MOSTLY IN THE NEAR
TERM ACROSS PORTIONS OF THE ADIRONDACKS...INCLUDING THE BLACK RIVER
BASIN...MOHAWK VALLEY AND MID HUDSON VALLEY REGIONS. THE SPRING
FLOOD POTENTIAL REMAINS ABOVE NORMAL ACROSS THE CONNECTICUT RIVER
BASIN AND PORTIONS OF THE NEARBY GREEN MOUNTAINS AS WELL AS NORTHERN
AND CENTRAL NEW HAMPSHIRE AND THE FOOTHILLS OF MAINE. WE ANTICIPATE
THE THREAT WILL IMPROVE TO NEAR NORMAL IN THE LONGER TERM.

THE SPRING FLOOD POTENTIAL IS WELL ABOVE NORMAL ACROSS NORTHERN AND
WESTERN MAINE.

THE POTENTIAL FOR FLOODING DUE TO ICE JAMS HAS PASSED FOR MOST OF
THE REGION...BUT THE THREAT REMAINS ABOVE NORMAL ACROSS NORTHERN
MAINE.


...CLIMATE GUIDANCE...

WARMER THAN NORMAL AVERAGE TEMPERATURES GENERALLY CHARACTERIZED THE
FIRST TWO WEEKS OF APRIL AFTER A COLDER THAN NORMAL MONTH OF MARCH.
AVERAGE TEMPERATURES DURING THE FIRST HALF OF APRIL GENERALLY RANGED
FROM 3 TO 4 DEGREES ABOVE NORMAL...EXCEPT JUST SLIGHTLY MILDER THAN
NORMAL ACROSS NORTHERN MAINE OVERALL.

ABOVE NORMAL PRECIPITATION WAS NOTED AGAIN ACROSS MOST OF NEW YORK
AND NEW ENGLAND. RECENTLY A VIGOROUS COLD FRONT ON APRIL 15TH HELPED
BRING A SURGE OF WARM AIR AND HEAVY RAINFALL TO MUCH OF NEW YORK
STATE AND NEW ENGLAND. PRECIPITATION TOTALS FOR THIS EVENT RANGED
FROM 1 TO 2 INCHES ACROSS MOST OF THE REGION.

THERE WILL BE AT LEAST A TEMPORARY REPRIEVE AS HIGH PRESSURE SETTLES
OVER THE REGION FOR A FEW DAYS. HOWEVER IT APPEARS AN ACTIVE PATTERN
WILL CONTINUE DURING LATE APRIL. SEVERAL PRECIPITATION THREATS
APPEAR POSSIBLE AS A SERIES OF LOW PRESSURE SYSTEMS EJECT EAST FROM
THE ROCKIES. HOWEVER POTENTIAL TIMING AND PHASING WILL BE CRITICAL
IN TERMS OF ANY POTENTIAL SIGNIFICANT RAINFALL THREAT.

IT IS ANTICIPATED THAT TEMPERATURES WILL AVERAGE CLOSER TO SEASONAL
NORMALS DURING THE NEXT TWO WEEKS WITH A SPLIT JET STREAM FLOW
PREVAILING.

THE OFFICIAL NATIONAL WEATHER SERVICE 8 TO 14 DAY OUTLOOK INDICATES
BEST CHANCES FOR NEAR NORMAL TEMPERATURES AND NEAR TO SLIGHTLY ABOVE
NORMAL PRECIPITATION DURING THE PERIOD.

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

THE RECENT WARMTH...ABOVE NORMAL RAINFALL AND HIGHER SUN ANGLE HAVE
ALL HELPED WORK TO DIMINISH MUCH OF THE SNOWPACK WHICH HAD BEEN
PLACE FOR MUCH OF THE WINTER ACROSS THE ADIRONDACKS OF UPSTATE NEW
YORK AND ACROSS NORTHERN NEW ENGLAND.

SNOW COVER AND SNOW DEPTHS HAVE DECREASED SUBSTANTIALLY ACROSS THE
REGION BUT PATCHY SNOW COVER STILL REMAINS PRIMARILY ACROSS PORTIONS
OF NORTHERN NEW YORK STATE AND NORTHERN NEW ENGLAND.

...NEW YORK STATE...

THE GROUND IS BARE ACROSS MOST OF SOUTHEASTERN NEW YORK INCLUDING
THE HUDSON VALLEY AND THE NEW YORK CITY METROPOLITAN AREA. SPOTTY
LIGHT SNOW COVER IS FOUND ACROSS THE CATSKILLS AND TACONICS...BUT
THIS WILL BE MELTING OFF SHORTLY. PATCHY SNOW COVER REMAINS ACROSS
NORTHERN AND WESTERN NEW YORK STATE INCLUDING THE ADIRONDACKS NORTH
COUNTRY AND THE FINGER LAKES REGION WHERE TRACE TO 4 INCH SNOW
DEPTHS ARE NOTED. LOCALLY HIGHER PATCHY AMOUNTS UP TO AROUND A FOOT
WERE STILL NOTED NEAR THE TUG HILL REGION. SNOW WATER EQUIVALENTS
GENERALLY RANGE FROM NIL TO LESS THAN AN INCH...EXCEPT LOCALLY UP TO
2 TO 6 INCHES ACROSS THE TUG HILL REGION.

...SOUTHERN NEW ENGLAND...

THE GROUND IS BARE ACROSS MOST OF CONNECTICUT...RHODE ISLAND AND
MASSACHUSETTS. LEFTOVER 1 TO 3 INCH SNOW DEPTHS WERE NOTED ACROSS
THE HIGH TERRAIN OF BERKSHIRES AND WORCESTER HILLS OF WESTERN AND
CENTRAL MASSACHUSETTS AND THE LITCHFIELD HILLS OF NORTHWEST
CONNECTICUT BUT THIS WILL BE MELTING OFF SHORTLY. SNOW WATER
EQUIVALENTS WERE LESS THAN 0.50 INCH ACROSS THESE AREAS.

...VERMONT AND NEW HAMPSHIRE...

THERE IS STILL PATCHY SNOW COVER REMAINING IN VERMONT...PRIMARILY
ACROSS THE HIGH TERRAIN OF THE NORTHERN GREEN MOUNTAINS INCLUDING
MOUNT MANSFIELD...STOWE AND WALDEN. SNOW DEPTHS RANGE FROM NIL SOUTH
TO 3 TO 6 INCHES NORTH...BUT LOCALIZED 1 FOOT PLUS AMOUNTS ARE NOTED
ACROSS THE HIGHEST TERRAIN. SNOW WATER EQUIVALENTS RANGE FROM NIL TO
LESS THAN ONE INCH MOST AREAS...EXCEPT 2 TO 6 INCHES ACROSS THE
HIGHER TERRAIN.

THE GROUND IS ALSO MOSTLY BARE ACROSS NEW HAMPSHIRE...EXCEPT PATCHY
SNOW COVER REMAINS ACROSS THE UPPER MERRIMACK...NORTHERN WHITE
MOUNTAINS AND ALSO NEARING THE CANADIAN BORDER. SNOW DEPTHS ACROSS
THESE AREAS RANGE FROM 2 TO 6 INCHES...BUT LOCALLY UP TO A FOOT
ACROSS THE HIGHEST TERRAIN. SNOW WATER EQUIVALENTS RANGE FROM NIL TO
LESS THAN ONE INCH MOST AREAS...EXCEPT 2 TO 6 INCHES ACROSS THE
HIGHER TERRAIN.

...MAINE...

THE GROUND IS BARE ALONG COASTAL MAINE WITH LIGHT PATCHY SNOWCOVER
ACROSS THE NEARBY FOOTHILLS. SNOW COVER IS STILL FAIRLY WIDESPREAD
NORTHERN AND WESTERN MAINE. HOWEVER SNOW DEPTHS HAVE SIGNIFICANTLY
DECREASED TO 5 TO 10 INCHES WITH LOCALIZED AMOUNTS FROM 12 TO 20
INCHES ACROSS THE HIGHER TERRAIN. SNOW WATER EQUIVALENTS ACROSS
NORTHERN AND WESTERN MAINE GENERALLY RANGE FROM 3 TO 6 INCHES...BUT
LOCALLY HIGHER FROM 6 TO 8 INCHES ACROSS THE HIGH TERRAIN. THE
HIGHEST SNOW WATER EQUIVALENTS WERE NOTE AT THE SAINT JOHN RIVER AT
NINE MILE BRIDGE AND BIG BLACK RIVER NEAR CLAYTON LAKE.

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

MILDER THAN NORMAL AVERAGE TEMPERATURES ALLOWED FOR INCREASED RUNOFF
AND EVAPORATION OF THE RECENT SNOWPACK IN PLACE ACROSS NORTHERN NEW
YORK STATE AND NORTHERN NEW ENGLAND DURING THE PAST TWO WEEKS. THE
MOST RECENT COLD FRONTAL PASSAGE BROUGHT THE MOST SIGNIFICANT RUNOFF
AND INFILTRATION. ABOVE NORMAL PRECIPITATION...MOSTLY IN THE FORM OF
RAIN OR MIXED PRECIPITATION IMPACTED NEW YORK AND NEW ENGLAND DURING
THE FIRST TWO WEEKS OF APRIL.

NEAR SURFACE SOIL MOISTURE MAPS AS OF 15 APRIL 2014 INDICATED NEAR
NORMAL SURFACE MOISTURE ANOMALIES ACROSS MOST OF NEW ENGLAND AND NEW
YORK STATE. NEAR SURFACE SOIL MOISTURE ANOMALIES ACROSS NORTHERN
MAINE ARE SLIGHTLY ABOVE NORMAL WHERE WIDESPREAD SNOWPACK STILL
REMAINS. MEANWHILE ACROSS WESTERN NEW YORK AND SOUTHERN NEW ENGLAND
WHERE SNOWPACK IS NO LONGER PRESENT...THE SOIL MOISTURE ANOMALIES
ARE SLIGHTLY BELOW NORMAL.

THE PALMER DROUGHT INDEX EXAMINES THE LONGER TERM SOIL MOISTURE
STATES OVER A PERIOD OF WEEKS TO SEVERAL MONTHS. THE PALMER INDEX AS
OF APRIL 12TH 2014 INDICATED MOIST CONDITIONS PRESENT ACROSS
PORTIONS OF CENTRAL AND SOUTHERN NEW ENGLAND AS WELL AS CENTRAL AND
WESTERN NEW YORK. NEAR NORMAL CONDITIONS PREVAILED ACROSS NORTHERN
AND EXTREME SOUTHEASTERN NEW YORK STATE...AND NORTHERN MAINE. VERY
MOIST CONDITIONS WERE STILL NOTED ACROSS THE FINGER LAKES REGION OF
CENTRAL NEW YORK.

EXAMINING GROUNDWATER MONITORING WELLS ACROSS THE REGION COURTESY OF
THE UNITED STATES GEOLOGICAL SURVEY (USGS)...

IN NEW YORK STATE GROUNDWATER LEVELS AS OF APRIL 16TH 2014 WERE
GENERALLY NEAR TO ABOVE NORMAL. A FEW LOCATIONS WERE REPORTING BELOW
NORMAL GROUNDWATER LEVELS INCLUDING MANCHESTER IN WESTERN NEW YORK
AND LOUISVILLE IN THE NORTH COUNTRY.

IN SOUTHERN NEW ENGLAND...GROUNDWATER LEVELS WERE REPORTED TO BE AT
OR ABOVE NORMAL LEVELS THANKS TO RECENT ABOVE NORMAL RAINFALL.

ACROSS NORTHERN NEW ENGLAND...GROUNDWATER LEVELS WERE NOW REPORTED
TO BE AT OR ABOVE NORMAL LEVELS. THIS INCLUDES MOST OF VERMONT...NEW
HAMPSHIRE AND INTERIOR MAINE. SIGNIFICANT SNOWMELT AND ABOVE NORMAL
PRECIPITATION DURING THE FIRST TWO WEEKS OF APRIL HELPED REPLENISH
THE WATER SUPPLY LEVELS.

RESERVOIR LEVELS...

IN NEW YORK STATE...THE NEW YORK CITY WATER SUPPLY SYSTEM WAS
RUNNING 96.9 PERCENT OF CAPACITY AS OF APRIL 15 2014. THIS IS 1.5
PERCENT BELOW NORMAL.

IN RHODE ISLAND...SCITUATE RESERVOIR WAS RUNNING ABOVE 100 PERCENT
CAPACITY. THE RESERVOIR POOL ELEVATION LEVEL AS OF 8AM APRIL 16TH
2014 WAS OBSERVED AT 285.8 FEET. THIS LEVEL IS 1.8 FEET ABOVE THE
SPILLWAY.

...RIVER AND ICE CONDITIONS...

AS OF APRIL 16TH 2014...STREAMFLOWS ACROSS NEW YORK STATE WERE
RUNNING AT OR ABOVE NORMAL LEVELS ALONG INTERSTATE 90 AND POINTS
SOUTH INCLUDING MOST OF WESTERN AND SOUTHERN NEW YORK STATE.
STREAMFLOWS ACROSS NORTHERN NEW YORK STATE...NORTH OF INTERSTATE 90
WERE ABOVE NORMAL LEVELS TO HIGH WATER LEVELS. IN FACT AS OF APRIL
16TH 2014 THERE WERE SEVERAL RIVER LOCATIONS AT OR ABOVE FLOOD STAGE
ACROSS THE MOHAWK AND MID HUDSON VALLEY REGIONS AS WELL AS THE BLACK
RIVER BASIN. MUCH OF THE REMAINING ICE ACROSS NORTHERN NEW YORK
STATE HAS BEEN FLUSHED OUT DUE TO THE RECENT WARMTH AND
MODERATE TO HEAVY RAINFALL.

STREAMFLOWS ACROSS SOUTHERN NEW ENGLAND RANGED FROM NORMAL TO ABOVE
NORMAL LEVELS. IN FACT SEVERAL LOCATIONS WERE IN FLOOD ALONG THE
LOWER CONNECTICUT RIVER AS OF APRIL 16TH 2014.

STREAMFLOWS ACROSS NORTHERN NEW ENGLAND NOW RANGE FROM NORMAL TO
ABOVE NORMAL. THERE ARE STILL SOME PARTIALLY ICE AFFECTED RIVERS
AND STREAMS ACROSS NORTHERN MAINE...INCLUDING THE SAINT JOHN RIVER
AT NINE MILE BRIDGE...ALLAGASH RIVER NEAR ALLAGASH...FISH RIVER
NEAR FORT KENT AND PORTIONS OF THE AROOSTOOK RIVER NEAR TINKER DAM.

SEVERAL POINTS WERE IN FLOOD AS OF APRIL 16 2014 ALONG THE MID TO
UPPER CONNECTICUT RIVER AND THE MISSISQUOI RIVER IN NEW HAMPSHIRE
AND VERMONT...THE ANDROSCOGGIN RIVER IN NEW HAMPSHIRE AND
MAINE...THE KENNEBEC RIVER... SEBASTICOOK RIVER...PISCATAQUIS
RIVER... PENOBSCOT RIVER AND MATTAWAMKEAG RIVER IN MAINE.

...CONCLUSION...

BASED ON THE INFORMATION AVAILABLE AT THIS TIME...

NEAR NORMAL SPRING FLOOD POTENTIAL IS FORECAST ACROSS WESTERN NEW
YORK...EXTREME SOUTHEASTERN NEW YORK STATE INCLUDING THE LOWER
HUDSON VALLEY AND MOST OF SOUTHERN NEW ENGLAND EXCEPT THE LOWER
CONNECTICUT RIVER BASIN.

ANTECEDENT CONDITIONS REMAIN NEAR NORMAL TO MOIST ACROSS THESE
AREAS. HOWEVER SNOWPACK IS NEARLY GONE ACROSS THIS REGION. IN
ADDITION GREENUP IS ANTICIPATED TO DEVELOP OVER THE NEXT COUPLE OF
WEEKS WHICH WILL ALLOW FOR INCREASED ABSORPTION AND
EVAPOTRANSPIRATION OF CURRENT MOISTURE LEVELS AND UPCOMING
PRECIPITATION THREATS.

ABOVE NORMAL SPRING FLOOD POTENTIAL IS FORECAST ACROSS PORTIONS OF
THE ADIRONDACKS...INCLUDING THE BLACK RIVER BASIN...MOHAWK VALLEY
AND MID HUDSON VALLEY REGIONS. IN ADDITION THE SPRING FLOOD
POTENTIAL REMAINS ABOVE NORMAL ACROSS THE CONNECTICUT RIVER BASIN
AND PORTIONS OF THE NEARBY GREEN MOUNTAINS AS WELL AS NORTHERN NEW
HAMPSHIRE AND THE FOOTHILLS OF MAINE.

ANTECEDENT CONDITIONS REMAIN NEAR NORMAL TO MOIST ACROSS THESE AREAS
WITH ABOVE NORMAL STREAMFLOWS OBSERVED DUE TO SNOWMELT AND ABOVE
NORMAL PRECIPITATION. SOME PATCHY SNOWCOVER REMAINS ACROSS THESE
AREAS. GREENUP HAS BEEN SOMEWHAT DELAYED PARTLY DUE TO THE COLDER
THAN NORMAL MARCH. ANY UPCOMING SIGNIFICANT RAIN THREAT WOULD
TRANSLATE INTO FAIRLY QUICK RUNOFF IN THE NEAR TERM DUE TO THE
NEARLY SATURATED GROUND. WE ALSO EXPECT THE HIGH SUN ANGLE TO
CONTINUE TO GRADUALLY MELT AWAY ANY OF THE REMAINING SNOWPACK INTO
THE RIVERS AND STREAMS.

WELL ABOVE NORMAL SPRING FLOOD POTENTIAL IS FORECAST ACROSS
PORTIONS OF NORTHERN AND WESTERN MAINE.

SNOWPACK AND RIVER ICE COVERAGE REMAINS SOMEWHAT ABOVE NORMAL FOR
THIS TIME OF YEAR AND GIVEN THE INCREASING SUN ANGLE AND POTENTIAL
FUTURE PRECIPITATION EVENTS OVER THE NEXT COUPLE OF WEEKS...THE
OUTLOOK REMAINS WELL ABOVE NORMAL FOR WESTERN AND NORTHERN MAINE.

THE POTENTIAL FOR FLOODING DUE TO ICE JAMS HAS PASSED FOR MOST OF
THE REGION...BUT THE THREAT REMAINS ABOVE NORMAL ACROSS NORTHERN
MAINE.

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 MAY 1 2014...IF DEEMED NECESSARY AT THAT TIME.

END/STRAUSS
$$



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