Flood Potential Outlook
Issued by NWS Portland, ME

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1
764
FGUS71 KGYX 051841
ESFGYX
MEC001-005-007-011-013-015-017-023-025-027-031-NHC001-003-005-007-
009-011-013-015-017-019-071845-

WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE GRAY ME
141 PM EST Thu Jan 5 2017

...WINTER/SPRING FLOOD POTENTIAL OUTLOOK...

THE FLOOD POTENTIAL IS NORMAL FOR WESTERN MAINE AND CENTRAL AND
NORTHERN NEW HAMPSHIRE. FLOOD POTENTIAL IS BELOW NORMAL IN
SOUTHERN NEW HAMPSHIRE. THE POTENTIAL FOR ICE JAM FLOODING IS NEAR
NORMAL.

THIS IS THE FIRST IN A SERIES OF REGULARLY SCHEDULED FLOOD
POTENTIAL OUTLOOKS THAT ARE ISSUED DURING THE WINTER AND SPRING
SEASONS. THESE OUTLOOKS WILL BE ISSUED EVERY TWO WEEKS UNTIL THE
END OF THE SNOW MELT SEASON... AND WILL ASSESS THE POTENTIAL FOR
FLOODING BASED A NUMBER OF FACTORS.

...CLIMATOLOGICAL GUIDANCE...

MAINE AND NEW HAMPSHIRE HAVE SEEN A MORE ACTIVE WEATHER PATTERN
RECENTLY. DECEMBER WAS A VERY SNOWY MONTH DUE MAINLY TO ONE STORM
AT THE END OF THE MONTH. THIS ACTIVE PATTERN IS EXPECTED TO
CONTINUE. HOWEVER THE STORM TRACK MAY BE WEST OF NEW ENGLAND
RESULTING IN MIXED PRECIPITATION EVENTS. WE EXPECT TO BE QUITE
COLD THROUGH MONDAY NEXT WEEK THEN SLOW WARMING WILL BEGIN.

THE OFFICIAL NATIONAL WEATHER SERVICE 6 TO 10 FORECAST AND 8 TO
14 DAY FORECAST CALLS FOR ABOVE NORMAL TEMPERATURES AND ABOVE
NORMAL PRECIPITATION.

...OBSERVED SNOW DEPTH AND WATER EQUIVALENT...

...NEW HAMPSHIRE...

SNOW DEPTHS ACROSS SOUTHERN NEW HAMPSHIRE RUNNING BETWEEN A TRACE
AND 6 INCHES. ACROSS THE REMAINDER OF NEW HAMPSHIRE SNOW DEPTHS
AVERAGE 8 TO 16 INCHES IN MOST VALLEY LOCATIONS WITH 1 TO 2 FEET
OR MORE IN THE HIGHER ELEVATIONS. THE HIGHEST SNOW DEPTHS ARE
FOUND FROM THE WHITE MOUNTAINS NORTH TO THE CANADIAN BORDER.
A RECENT REPORT FROM HERMIT LAKE AT ELEVATION OF 3750 FEET ON THE
SLOPES OF MOUNT WASHINGTON INDICATED 53 INCHES OF SNOW. MOOSE
FALLS IN NORTHERN NEW HAMPSHIRE REPORTED 25 INCHES OF SNOW.
SNOW DEPTHS ACROSS CENTRAL AND NORTHERN NEW HAMPSHIRE ARE NEAR
NORMAL. SNOW DEPTHS IN SOUTHERN NEW HAMPSHIRE ARE GENERALLY BELOW
NORMAL.

ACROSS SOUTHERN NEW HAMPSHIRE SNOW WATER EQUIVALENTS AVERAGE
BETWEEN A TRACE AND 2 INCHES. FOR CENTRAL AND NORTHERN NEW
HAMPSHIRE SNOW WATER EQUIVALENTS RANGE FROM 2 TO 5 INCHES WITH
ISOLATED HIGHER AMOUNTS ABOVE 1500 FEET. A SNOW WATER EQUIVALENT
REPORT FROM HARVARD CABIN AT AN ELEVATION OF 3500 FEET SHOWED 9
INCHES OF WATER IN 35 INCHES OF SNOW. AT MOOSE FALLS THE 25 INCHES
OF SNOW THERE HAD 6.6 INCHES OF WATER IN IT. SNOW WATER
EQUIVALENTS ARE NEAR NORMAL FOR CENTRAL AND NORTHERN NEW HAMPSHIRE
AND GENERALLY BELOW NORMAL IN SOUTHER LOCATIONS.

...WESTERN MAINE...

SNOW DEPTH ALONG THE IMMEDIATE COASTLINE IS GENERALLY LESS THAN 6
INCHES. SNOW DEPTH INCREASES RAPIDLY AWAY FROM THE COAST WHERE 1
TO 3 FEET OF SNOW IS ON THE GROUND. SOME OF THE HIGHER AMOUNTS
INCLUDE KINGFIELD AT 41 INCHES AND ANDOVER AT 29 INCHES.

SNOW WATER EQUIVALENTS ALONG THE IMMEDIATE COASTLINE ARE
GENERALLY LESS THAN 2 INCHES AND INCREASES RAPIDLY INLAND TO 3 TO
6 INCHES OF WATER. UP TO 8 INCHES OF WATER EQUIVALENT IS LIKELY
ABOVE ABOUT 2500 NEAR THE CANADIAN BORDER. SNOW WATER EQUIVALENTS
ARE GENERALLY ABOVE NORMAL EXCEPT RIGHT ALONG THE COAST WHERE
THEY ARE NEAR TO BELOW NORMAL FOR EARLY JANUARY.

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

SOIL MOISTURE ANOMALY MAPS INDICATE THAT SOIL MOISTURE HAS
IMPROVED TO NORMAL ACROSS ALL OF WESTERN MAINE EXCEPT SOUTHERN
YORK COUNTY WHERE IT IS STILL BELOW NORMAL. IN NEW HAMPSHIRE SOIL
MOISTURE REMAINS BELOW NORMAL EXCEPT FOR NORTHEAST COOS COUNTY
WHERE IT IS NORMAL.

THE LONGER TERM PALMER DROUGHT SEVERITY INDEX IS INDICATING NEAR
NORMAL MOISTURE CONDITIONS FOR WESTERN MAINE AND NEW HAMPSHIRE.

RESERVOIRS IN THE KENNEBEC RIVER BASIN ARE ABOVE NORMAL LEVELS
FOR THE TIME.

RESERVOIRS IN THE ANDROSCOGGIN RIVER BASIN ARE 65.7 PERCENT FULL
WHICH IS 5 PERCENT ABOVE NORMAL.

GROUNDWATER LEVELS COURTESY OF THE USGS ARE BELOW NORMAL FOR THE
TIME OF YEAR.

GROUNDWATER SUPPLY SHORTAGES ARE POSSIBLE IN THE SPRING UNLESS WE
RECEIVE AT LEAST A FEW MONTHS OF ABOVE NORMAL PRECIPITATION
DURING THE WINTER. HAVING A SUBSTANTIAL SNOW COVER IN THE SPRING
WOULD HELP TO ALLEVIATE ANY GROUNDWATER SHORTAGES.

...RIVER AND ICE CONDITIONS...

RIVER FLOWS ARE NEAR NORMAL FOR THE TIME OF YEAR.

ICE COVER HAS INCREASED OVER THE PAST FEW WEEKS WITH NEAR NORMAL
DECEMBER TEMPERATURES AND HAS BECOME WELL ESTABLISHED. ICE
THICKNESS IS THOUGHT TO BE ANY WHERE FROM 6 TO 8 INCHES. HOWEVER
WE HAVE NOT RECEIVED ANY RECENT REPORTS. ICE THICKNESS IS ABOUT
NORMAL FOR THE TIME OF YEAR. WE EXPECT TO GET SOME REPORTS OVER
THE NEXT 2 WEEKS.

...IN CONCLUSION...

BASED ON THE ABOVE INFORMATION...THE WINTER/SPRING FLOOD
POTENTIAL IS NEAR NORMAL FOR NORTHERN AND CENTRAL NEW HAMPSHIRE
AND FOR WESTERN MAINE. FLOOD POTENTIAL IS BELOW NORMAL FOR
SOUTHERN NEW HAMPSHIRE. THE POTENTIAL FOR ICE JAM FLOODING IS
NORMAL.

IT IS IMPORTANT TO NOTE THAT MAJOR FLOODING DOES NOT OCCUR FROM
SNOWMELT ALONE. RAINFALL...HOW MUCH AND IN HOW SHORT A PERIOD OF
TIME...IS THE MOST IMPORTANT FACTOR IN DETERMINING THE SEVERITY
OF FLOODING.

ANOTHER WINTER/SPRING FLOOD POTENTIAL OUTLOOK WILL BE ISSUED BY 8
AM FRIDAY JANUARY 20.

$$

TFH



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