Hydrometeorological Discussion
Issued by NWS Northeast RFC

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
000
AGUS71 KTAR 211556
HMDTAR
HYDROMETEOROLOGICAL DISCUSSION
NATIONAL WEATHER SERVICE
NORTHEAST RIVER FORECAST CENTER...TAUNTON...MA
1154 AM EDT TUE OCT 21 2014

HYDROMETEOROLOGICAL DISCUSSION:
:
14Z( 10 AM EDT ) MESOSCALE ANALYSIS INDICATING LOW PRESSURE ACROSS
CENTRAL/WESTERN NY..THIS LOW WILL DROP SOUTHEAST AND THEN
REDEVELOP SOUTH OF NEW ENGLAND BY THIS EVENING. AS THIS NEW LOW
DEVELOPS...UPPER LEVEL ENERGY WILL CUTOFF CAUSING THE STORM TO
MEANDER ABOUT RIGHT INTO FRIDAY NEAR OR JUST OFF THE EAST COAST OF
NEW ENGLAND.
:
NUMERICAL WEATHER PREDICTION MODELS SHOW THE BEST ATLANTIC INFLOW
AND MOIST CONVEYOR BELT TARGETING AREAS OF CENTRAL AND WESTERN
MAINE...THE MOUNTAINS OF NORTHERN NEW HAMPSHIRE AND PERHAPS THE
MOUNTAINS OF NORTHERN VERMONT IN THE WEDNESDAY THROUGH FRIDAY TIME
FRAME AND THOSE AREAS ARE LIKELY TO SEE THE HEAVIEST RAINFALL
FROM THIS SYSTEM. BASIN AVERAGE RAINFALL THROUGH 8 AM EDT FRIDAY
IS EXPECTED TO BE IN THE 2.00 - 4.00 INCH RANGE ACROSS THE CENTRAL
AND WESTERN FOOTHILLS OF MAINE SOUTH TO THE COAST WITH ADDITIONAL
HEAVY RAINFALL POSSIBLE THURSDAY INTO FRIDAY.
:
NERFC METEOROLOGISTS AND HYDROLOGISTS WILL NEED TO MONITOR THE
PROGRESS OF THIS SYSTEM CLOSELY THIS WEEK SINCE RAINFALL COULD
BECOME HEAVY ENOUGH TO PRODUCE SIGNIFICANT RISES ON AREA RIVERS
AND STREAMS...ESPECIALLY ACROSS NORTHERN NEW ENGLAND AND PERHAPS
NORTHERN NEW YORK STATE AS WELL.
:
HYDROLOGIC DISCUSSION:
:
AS LOW PRESSURE DEVELOPS AND INTENSIFIES SOUTH OF NEW ENGLAND,
RAINFALL IS EXPECTED TO OVERSPREAD EASTERN NEW ENGLAND PRIMARILY.
THE GREATEST RISING RIVER RESPONSES ARE FORECAST FOR LOCATIONS
ACROSS NEW HAMPSHIRE AND CENTRAL TO WESTERN MAINE. ANTECEDENT
CONDITIONS IN THESE AREAS ARE WETTER THAN EARLIER IN THE MONTH
WITH RECENT RAINFALL LATE LAST WEEK AND OVER THE WEEKEND. FURTHER,
EVAPOTRANSPIRATION CONTINUES TO DECLINE WITH THE LOSS OF LEAF
COVER. THUS, RISING RIVER RESPONSES ARE MORE LIKELY TO EXCEED THE
RECENT RISES LAST WEEKEND WITH THE ANTICIPATED PRECIPITATION AND
THE INCREASED RUNOFF.
:
MOST RISING RIVER RESPONSES ARE FORECAST TO REMAIN BELOW BANK-FULL
LEVELS. HOWEVER, THE PRECIPITATION AND RUNOFF MAY BE SUFFICIENT
FOR RIVER LEVELS OF RAPIDLY RESPONDING HEADWATER AND SMALLER
TRIBUTARY RIVERS TO EXCEED MINOR FLOOD LEVELS AT AN ISOLATED RIVER
FORECAST LOCATION OR TWO, PARTICULARLY IN MAINE AND NEW HAMPSHIRE
. THIS INCLUDES BUT IS NOT LIMITED TO FORECAST LOCATIONS FOR THE
PEMIGEWASSET RIVER AT WOODSTOCK, NH, SACO RIVER AT CONWAY, NH, AND
SWIFT RIVER AT ROXBURY, ME.
:
DRY CONDITIONS ACROSS MOST OF NEW ENGLAND DURING THE DAY YESTERDAY
AND OVERNIGHT ALLOWED RIVER LEVELS TO RECEDE FURTHER. OVERALL,
RIVER LEVELS RECEDED EVEN WHERE BASINS RECEIVED SOME RAINFALL
OVERNIGHT IN NEW YORK STATE AND VERMONT. RECEDING TRENDS VARIED
ANYWHERE FROM RAPIDLY TO SLOWLY AT FORECAST LOCATIONS. THERE WERE
ONLY A FEW FORECAST LOCATIONS IN WESTERN NEW YORK WHERE BASINS
RECEIVED SUFFICIENT RAINFALL TO RESULT IN MINOR, LESS THAN 1 FOOT
RISING RESPONSES PRIOR TO 8AM THIS MORNING. FLUCTUATIONS OF
SEVERAL FEET OCCURRED FOR FORECAST LOCATIONS DOWNSTREAM OF DAMS OR
AT LOCATIONS WITHIN THE INFLUENCE OF THE TIDAL CYCLE.
:
ACCORDING TO THE USGS WATER WATCH WEBPAGE... 7-DAY AVERAGE
STREAMFLOWS RELATIVE TO THOSE OCCURRING HISTORICALLY FOR MONDAY,
10/20 ARE IN THE NORMAL TO WELL ABOVE NORMAL RANGES ACROSS MOST OF
NEW YORK STATE AND NEW ENGLAND. RECENT RAINFALL AND INCREASED
RIVER FLOWS HAVE PROVIDED FOR SEVERAL LOCATIONS WITH WELL ABOVE
NORMAL FLOWS SITUATED ACROSS CENTRAL NEW YORK STATE, WESTERN MAINE
, MUCH OF NEW HAMPSHIRE AND WESTERN TO CENTRAL MASSACHUSETTS.
SEVERAL LOCATIONS IN SOUTHERN RHODE ISLAND, EASTERN MASSACHUSETTS,
AND EASTERN NEW YORK STATE RECORDED WEEKLY AVERAGE STREAMFLOWS
BELOW NORMAL LEVELS.
:
FLOOD OUTLOOK DISCUSSION:
:
THE NERFC FLOOD POTENTIAL OUTLOOK GRAPHIC INDICATES SIGNIFICANT
RIVER FLOODING IS NOT EXPECTED IN THE NORTHEASTERN UNITED STATES
DURING THE NEXT FIVE DAYS.
:
THE FLOOD OUTLOOK GRAPHIC IS AVAILABLE ON THE WEB AT:
:
HTTP://WWW.WEATHER.GOV/NERFC/FOP
:
ADDITIONAL WATER AND WEATHER RELATED INFORMATION CAN BE FOUND ON
THE NWS/NERFC HOME PAGE AT http://www.nws.noaa.gov/er/nerfc
:
$$
:
HYDROMETEOROLOGICAL DISCUSSION:       ED CAPONE
HYDROLOGIC DISCUSSION:                ERICK BOEHMLER




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