Public Information Statement
Issued by NWS Portland, ME

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NOUS41 KGYX 191537
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MEZ007>009-012>014-018>022-023>028-NHZ001>010-013-014-201200

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE GRAY ME
1100 AM EST WED MAR 19 2014

THE NATIONAL WEATHER SERVICE HAS DECLARED THE WEEK OF MARCH
16TH THROUGH 22ND FLOOD AWARENESS WEEK IN MAINE AND NEW
HAMPSHIRE, AS WELL AS THE REMAINDER OF THE UNITED STATES.

...DETERMINING THIS YEAR`S CURRENT CONDITIONS AND FLOOD
POTENTIAL...

TO HELP DETERMINE THE POTENTIAL FOR FLOODING, THE NATIONAL
WEATHER SERVICE OFFICES THAT SERVE NORTHERN NEW ENGLAND
CONTINUALLY MONITOR HYDROLOGICAL CONDITIONS THROUGHOUT THE
REGION.  RIVER STATEMENTS ARE ISSUED DAILY AND CONTAIN
FORECASTS OF THE WATER LEVELS FOR THE MAJOR RIVERS IN THE AREA.
ALSO, DURING THE LATE WINTER AND EARLY SPRING THE NATIONAL
WEATHER SERVICE, IN COORDINATION WITH OTHER FEDERAL AND STATE
AGENCIES, POWER COMPANIES, AND COOPERATIVE OBSERVERS, SURVEYS
THE SNOW PACK ACROSS THE AREA TO DETERMINE THE POTENTIAL FOR
SPRING FLOODING.

THERE ARE SEVERAL FACTORS THAT CONTRIBUTE TO THE SPRING FLOOD
POTENTIAL.  THESE INCLUDE THE AMOUNT OF SNOW ON THE GROUND, THE
AMOUNT OF WATER CONTAINED IN THE SNOW (OFTEN REFERRED TO AS
WATER EQUIVALENT OR WATER CONTENT), THE DENSITY OF THE
SNOWPACK, AND CURRENT RIVER AND STREAM LEVELS.  THE WATER
EQUIVALENT OF THE SNOWPACK REPRESENTS THE WATER THAT WILL BE
RELEASED AS THE SNOW MELTS.  THE DENSITY OF THE SNOW IS AN
INDICATION OF WHETHER ANY MELTED SNOW (OR SUBSEQUENT RAIN) CAN
BE ABSORBED BY THE SNOWPACK, OR WILL BE RELEASED.  ANOTHER
FACTOR IS HOW FAST THE SNOW WILL MELT.  AS A GENERAL RULE, THE
RATE OF MELTING IS RELATED TO THE TEMPERATURE, HUMIDITY, AND
WIND.  WARM TEMPERATURES ACCOMPANIED BY HIGH HUMIDITY AND WIND
CAUSE THE GREATEST AMOUNT OF MELTING.   IN ADDITION, THE STATE
OF THE SOIL (FROZEN VERSUS THAWED AND SATURATED VERSUS
UNSATURATED) DETERMINES WHETHER ANY MELTING SNOW WILL BE
ABSORBED BY THE GROUND.  MOST IMPORTANTLY, HOWEVER, THE
GREATEST CONTRIBUTING FACTOR TO FLOOD POTENTIAL IS RAINFALL.
IN NEW ENGLAND, MAJOR FLOODING DOES NOT OCCUR DUE SOLELY TO
MELTING SNOW.

IN ADDITION, FLOODING CAN OCCUR DUE TO ICE JAMS.  ICE JAMS TEND
TO OCCUR IN THE SPRING WHEN WATER LEVELS ON RIVERS START TO
RISE AND WHEN THERE IS STILL A SIGNIFICANTLY THICK LAYER OF ICE
ON THE RIVERS.  THE RISING WATER IN RIVERS CAUSES THE ICE TO
BREAK UP, ALLOWING LARGE CHUNKS OF ICE TO START FLOWING.  THESE
CHUNKS OF ICE CAN JAM AS THEY FLOW DOWNSTREAM.  THE JAMMED ICE
CAN THEN ACT AS A DAM AND CAN PREVENT WATER AND ICE FROM
FLOWING DOWNSTREAM.  ICE JAMS ARE UNPREDICTABLE AND WATER
BEHIND ICE JAMS CAN RISE VERY QUICKLY.  IN ADDITION, WHEN AN
ICE JAM BREAKS UP, THE RESULTING RELEASE CAN FLOOD DOWNSTREAM
AREAS VERY RAPIDLY.

PLEASE NOTE THAT THE FOLLOWING INFORMATION ON CURRENT
CONDITIONS IS BASED ON SNOW SURVEYS TAKEN MARCH 10TH AND 11TH.
PLEASE REFER TO THE FOLLOWING WEB SITE (IN LOWER CASE) FOR THE
LATEST SNOW CONDITIONS IN MAINE AND PORTIONS OF NEW HAMPSHIRE

HTTP://WWW.MAINE.GOV/MEMA/WEATHER/SNOW.HTM

THE FOLLOWING WEB SITE (IN LOWER CASE) PROVIDES UP-TO-DATE
RIVER AND FLOOD INFORMATION.

HTTP://WEATHER.GOV/NERFC

THE FOLLOWING WEB SITE PROVIDES INFORMATION ON ICE JAMS.

HTTP://ICEJAMS.CRREL.USACE.ARMY.MIL/


CURRENT CONDITIONS:

.CURRENT SNOW DEPTH AND WATER EQUIVALENT...SNOW DEPTHS ACROSS
WESTERN MAINE AND NEW HAMPSHIRE RANGE FROM 8 TO 24 INCHES IN
SOUTHERN AND COASTAL AREAS TO 20 TO 48 INCHES IN CENTRAL AND
NORTHERN NEW HAMPSHIRE AND THE WESTERN MOUNTAINS OF MAINE.
THE WATER EQUIVALENT OF THE SNOWPACK RANGES FROM 3 TO 7 INCHES
IN THE SOUTH AND ALONG THE COAST TO 6 TO 10 INCHES WITH
LOCALLY HIGHER AMOUNTS IN THE MOUNTAINS.  THESE VALUES ARE
ABOVE NORMAL FOR THIS TIME OF YEAR.

.CURRENT SNOW DENSITY...THE DENSITY OF THE SNOWPACK GENERALLY
RANGES FROM ABOUT .25 IN THE MOUNTAINS TO ABOUT .40 ALONG THE
COAST.  A SNOW PACK WITH A DENSITY OF AT OR ABOVE .35 IS
CONSIDERED "RIPE" BECAUSE IT WILL HOLD NO MORE WATER AND ANY
RAINFALL OR MELTING WITH RESULT IN RUNOFF.

.CURRENT RIVER LEVELS...WATER LEVELS AND FLOWS IN RIVERS AND
STREAMS THROUGHOUT MAINE AND NEW HAMPSHIRE ARE NEAR TO
SOMEWHAT BELOW NORMAL FOR THIS TIME OF YEAR.

.FORECAST TEMPERATURES AND PRECIPITATION...TEMPERATURES ARE
EXPECTED TO REMAIN BELOW NORMAL FOR THE TIME OF YEAR THROUGH
NEXT WEEK. THERE WILL BE SEVERAL CHANCE FOR SNOW OR MIXED
PRECIPITATION THAT WILL LIKELY ADD TO THE SNOWPACK DURING THIS
TIME.  TEMPERATURES FOR THE NEXT 6 TO 10 DAYS ARE
FORECAST TO BE BELOW NORMAL. DURING THIS TIME, PRECIPITATION IS
EXPECTED TO BE NEAR NORMAL. THE PROLONGED COLD TEMPERATURES
AND ANY ADDITIONAL PRECIPITATION ARE BOTH INCREASING THE
POTENTIAL FOR FLOODING LATER THIS SPRING.

.RIVER ICE AND ICE JAM POTENTIAL...THE COLD WINTER TEMPERATURES
CONTINUE TO CAUSE ICE TO THICKEN IN MANY RIVERS ACROSS WESTERN
MAINE AND NEW HAMPSHIRE.  ICE THICKNESSES ARE ABOVE NORMAL FOR
THIS TIME OF YEAR AND RANGE FROM 1 TO 2 FEET. THESE CONDITIONS,
ALONG WITH THE CONTINUED COLD TEMPERATURES EXPECTED DURING THE
NEXT 10 DAYS, RAISES THE RISK FOR SIGNIFICANT ICE JAM FLOODING
LATER THIS SPRING.

.FLOOD POTENTIAL OUTLOOK...THE OVERALL SPRING FLOOD POTENTIAL
ACROSS MAINE AND NEW HAMPSHIRE IS ABOVE NORMAL.  AT THIS
TIME, THE GREATEST CONCERN IS THAT THE CHANCE FOR WARM
TEMPERATURES AND A RAPID SNOWMELT INCREASES AS WE GET LATER IN
THE SEASON.

FLOODING IS THE TOP STORM-RELATED KILLER IN THE UNITED STATES.
MANY FATALITIES OCCUR BECAUSE PEOPLE ATTEMPT TO DRIVE THROUGH
FLOODED ROADWAYS.  REMEMBER, IF YOU ENCOUNTER A FLOODED ROAD,
TURN AROUND, DON`T DROWN!

$$


JENSENIUS/HAWLEY
NATIONAL WEATHER SERVICE
GRAY, MAINE

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