Winter and Spring Flood Potential Outlook issued on March 6th

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WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE CARIBOU ME
522 PM EST THU MAR 6 2014

...WINTER AND SPRING FLOOD POTENTIAL OUTLOOK FOR NORTHERN...
CENTRAL AND DOWNEAST MAINE...

THIS IS THE FIFTH WINTER/SPRING FLOOD POTENTIAL OUTLOOK FOR
2014...ISSUED BY THE NATIONAL WEATHER SERVICE IN CARIBOU, MAINE.
THE WINTER/SPRING FLOOD POTENTIAL IS FOR NORTHERN, CENTRAL AND
DOWNEAST MAINE FOR THE TWO WEEK PERIOD FROM MARCH 6 TO MARCH 20,
2014.

THE WINTER/SPRING FLOOD POTENTIAL FOR NORTHERN, CENTRAL AND
DOWNEAST MAINE IS NEAR NORMAL THROUGH THE NEAR TERM, THOUGH IT IS
SOMEWHAT ABOVE NORMAL THROUGH THE LONG TERM. LIKEWISE, THE
POTENTIAL FOR FLOODING DUE TO ICE JAMS ACROSS THE REGION IS NEAR
NORMAL IN THE NEAR TERM BUT ABOVE NORMAL GOING FORWARD THROUGH SPRING.

...CLIMATOLOGICAL GUIDANCE...

THE LATTER PART OF FEBRUARY INTO EARLY MARCH HAS GENERALLY BEEN
VERY COLD AND DRY WITH JUST OCCASIONAL LIGHT SNOW SHOWERS SEEN
OVER NORTHERN MAINE. TEMPERATURES HAVE BEEN WELL BELOW NORMAL OVER
THE PAST TWO WEEKS, WITH DAILY TEMPERATURES AVERAGING 10 TO 20
DEGREES BELOW NORMAL. ALTHOUGH A RETURN TO NEAR NORMAL
TEMPERATURES IS EXPECTED FOR THIS WEEKEND, THE WARMER WEATHER WILL
BE BRIEF, AS INDICATIONS ARE THAT COLDER THAN NORMAL CONDITIONS
WILL PREVAIL THROUGH MID MARCH. IN ADDITION, THE PATTERN LOOKS TO
REMAIN ACTIVE OVER THE NEXT COUPLE OF WEEKS WITH SEVERAL CHANCES
FOR PRECIPITATION. GIVEN THE COLD, IT IS EXPECTED THIS
PRECIPITATION WOULD MAINLY FALL AS SNOW. THE OFFICIAL NATIONAL
WEATHER SERVICE 8-14 DAY OUTLOOK MATCHES THIS THINKING WELL,
CALLING FOR BELOW NORMAL TEMPERATURES AND ABOVE NORMAL
PRECIPITATION FOR ALL OF NORTHERN AND EASTERN MAINE.

...OBSERVED SNOW DEPTH AND WATER EQUIVALENTS...

SNOW DEPTHS AND WATER EQUIVALENTS ARE NEAR NORMAL ACROSS THE
STATE. WITH LITTLE IN THE WAY OF SIGNIFICANT SNOWFALL REPORTED
RECENTLY, THE SNOWPACK HAS ACTUALLY DECREASED A BIT AS THE
SNOWFALL FROM EARLIER IN THE MONTH HAS SETTLED.

DOWNEAST MAINE GENERALLY HAS 10 TO 18 INCHES OF SNOW COVERING THE
GROUND, WITH A BIT LESS ALONG THE COAST. THE DEPTHS INCREASE TO
18 TO 24 INCHES AS YOU HEAD INTO THE CENTRAL HIGHLANDS, WITH SOME
REGIONS REPORTING UP T0 30 INCHES. AROOSTOOK COUNTY AND THE NORTH
MAINE WOODS ARE COVERED BY 20 TO 30 INCHES OF SNOW, WITH THE FAR
NORTHERN CROWN APPROACHING 3 FEET IN SPOTS. THESE AMOUNTS ARE ALL
NEAR NORMAL FOR EARLY MARCH.

THE SNOW WATER EQUIVALENT, OR THE AMOUNT OF WATER CONTAINED IN THE
SNOWPACK, IS ALSO NEAR NORMAL. DOWNEAST MAINE GENERALLY HAS 4 TO 6
INCHES OF WATER IN THE SNOW, WHILE INTERIOR AREAS UP THROUGH THE
HIGHLANDS INTO NORTHERN MAINE ARE REPORTING 5 TO 8 INCHES. THESE
AMOUNTS, TOO, ARE NEAR NORMAL FOR THIS TIME OF YEAR. 

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

WITH THE COLD WEATHER WE'VE EXPERIENCED OVER THE PAST SEVERAL 
WEEKS, THERE HAS BEEN VERY LITTLE RUNOFF FROM EITHER RAIN OR
SNOWMELT. SOIL MOISTURE STATES ARE MAINLY NEAR NORMAL, THOUGH
NORTHERN MAINE IS STILL SHOWING SLIGHTLY WETTER THAN NORMAL SOIL
MOISTURE. THE LONGER TERM PALMER DROUGHT INDEX RELEASED MARCH 1ST
SHOWS MUCH OF THE REGION NEAR NORMAL, WITH CENTRAL AND DOWNEASTERN
MAINE WETTER THAN NORMAL. 


...RIVER AND ICE CONDITIONS...

SINCE TEMPERATURES HAVE REMAINED COLD ENOUGH OVER THE PAST
SEVERAL DAYS TO LIMIT ANY SIGNIFICANT SNOWMELT AND KEEP
ANY PRECIPITATION IN THE FORM OF SNOW, RIVER FLOWS CONTINUE TO
HOLD STEADY OR EVEN FALL SLIGHTLY OWING TO LITTLE TO NO RECENT RUNOFF.
THIS TREND IS EXPECTED TO CONTINUE OVER THE NEXT COUPLE OF WEEKS.
WHILE A WARM UP IS EXPECTED THROUGH THE WEEKEND, THE MILD SPELL
WILL BE BRIEF AND THEREFORE LIMIT ANY SNOWMELT AND ANY RESULTANT
RUNOFF.

THE ICE ALONG THE NORTHERN WATERWAYS, INCLUDING THE ALLAGASH,
SAINT JOHN, AND AROOSTOOK RIVERS, CONTINUES TO STRENGTHEN.
THICKNESSES IN THESE RIVERS IS GENERALLY 1.5 TO AROUND 2 FEET
THICK, WITH THE UPPER REACHES PERHAPS APPROACHING 30 INCHES IN SPOTS.
THIS IS GENERALLY NORMAL FOR THIS TIME OF YEAR. WITH COLD WEATHER
TO CONTINUE, THE ICE WILL LIKELY CONTINUE TO SLOWLY BUILD OVER
THE NEXT COUPLE OF WEEKS.

FURTHER SOUTH, THE CENTRAL RIVERS SUCH AS THE PISCATAQUIS AND
PENOBSCOT GENERALLY HAVE 1 TO 1.5 FEET OF ICE. THE LOWER REACHES
OF THESE RIVERS WHICH EXPERIENCED BREAKUP DURING THE JANUARY THAW
HAVE 6 TO 10 INCHES OF ICE. HOWEVER, SOME STRETCHES, EVEN THOSE IN
THE UPPER REACHES, ARE PARTIALLY OPEN WITH FAIRLY THIN AND/OR WEAK
ICE. FAR DOWNEAST RIVERS HAVE 1 FOOT OF ICE OR LESS. THESE CENTRAL
AND SOUTHERN WATERWAYS HAVE LESS ICE THAN NORMAL FOR MID MARCH.
LIKE THE NORTHERN RIVERS, THE CONTINUED COLD WILL ALLOW THE ICE IN
THESE AREAS TO AT LEAST HOLD STEADY OVER THE NEXT COUPLE OF WEEKS,
IF NOT BUILD SOMEWHAT.

SEVERAL JAMS REMAIN LOCKED IN PLACE ACROSS CARIBOU'S FORECAST
AREA. THESE INCLUDE BUT ARE NOT LIMITED TO ICE JAMS ALONG THE
SAINT JOHN RIVER UPSTREAM OF FORT KENT, THE EAST BRANCH OF THE
PENOBSCOT RIVER DOWNSTREAM OF GRINDSTONE, THE PENOBSCOT RIVER NEAR
WINN, THE PISCATAQUIS RIVER UPSTREAM OF HOWLAND, AND THE
KENDUSKEAG STREAM IN DOWNTOWN BANGOR. THESE JAMS ARE NOW WELL
FROZEN IN PLACE AND ARE NOT EXPECTED TO MOVE OVER THE NEXT COUPLE
OF WEEKS. HOWEVER, SHOULD A PROLONGED WARM UP OCCUR, ESPECIALLY
ACCOMPANIED BY SIGNIFICANT RAINFALL, THESE EXISTING JAMS WILL
LIKELY SERVE AS A FOCUS FOR ADDITIONAL JAMMING AND POTENTIAL
FLOODING. IN ADDITION, THE ICE ALONG THE UNBROKEN STRETCHES IS
VERY WELL ESTABLISHED AND WHILE IT WILL TAKE MAJOR RIVER RISES TO
BREAK IT UP, IT WILL BE MORE SUSCEPTIBLE TO CAUSING JAMMING ONCE
IT DOES RELEASE.

...IN CONCLUSION...

BASED ON THE AFOREMENTIONED INFORMATION, THE SHORT-TERM
WINTER/SPRING FLOOD POTENTIAL IS NEAR NORMAL FOR ALL OF NORTHERN,
CENTRAL, AND DOWNEAST MAINE. RIVER FLOWS, GROUNDWATER LEVELS, AND
ANTECEDENT MOISTURE ARE ALL NEAR NORMAL. SNOW DEPTHS AND SNOW
WATER EQUIVALENTS ARE ALSO NEAR NORMAL. THE CURRENT WARM UP FORECASTED
FOR THE END OF THE WEEK IS NOT EXPECTED TO PROVIDE ENOUGH RUNOFF TO
BRING A SIGNIFICANT FLOODING THREAT. WITH COLD TEMPERATURES TO
RESUME NEXT WEEK AND HOLD INTO MID MARCH, IT LOOKS LIKE THE OVERALL
FLOOD POTENTIAL WILL REMAIN NEAR NORMAL. IT SHOULD BE NOTED,
THOUGH, THAT THE SNOWPACK MAY ACTUALLY INCREASE OVER THE NEXT COUPLE
OF WEEKS OWING TO THE CONTINUED COLD AND AN ACTIVE WEATHER
PATTERN. ANY PRECIPITATION WILL GENERALLY FALL AS SNOW. THEREFORE,
IN THE LONGER TERM, THE FLOOD POTENTIAL IS ABOVE NORMAL AS WE HAVE
BUILT UP AN EXTENSIVE SNOWPACK HEADING INTO THE SPRING MELT.

THE POTENTIAL FOR ICE JAM FLOODING IS ALSO NEAR NORMAL THROUGH
THE NEAR TERM. ALTHOUGH ICE JAMS EXIST ALONG SEVERAL RIVERS IN
CARIBOU'S FORECAST AREA, THESE JAMS ARE LOCKED IN PLACE. THE ICE
IS WELL ESTABLISHED ON THE SAINT JOHN, AROOSTOOK, AND ALLAGASH
WATERWAYS. ICE THICKNESSES ACROSS THE REGION ARE GENERALLY 1 TO AS
MUCH AS 3 FEET. AS MENTIONED EARLIER, THE NEAR-TERM WARM UP WILL
NOT BE SUBSTANTIAL ENOUGH TO MOVE ANY OF THIS ICE. WITH ARCTIC AIR
TO RETURN BY EARLY NEXT WEEK AND LINGER INTO MID MARCH, NO ICE
BREAKUP OR JAMMING IS EXPECTED THROUGH THE NEXT COUPLE OF WEEKS. IN
FACT, THE COLD AIR WILL ALLOW RIVER ICE TO AT LEAST HOLD FAIRLY
STEADY IF NOT CONTINUE TO SLOWLY BUILD. THIS MEANS WE WILL LIKELY
ENTER LATE MARCH WITH A SUBSTANTIAL AMOUNT OF RIVER ICE,
ESPECIALLY ACROSS THE NORTH. AS SUCH, THERE IS AN ABOVE NORMAL THREAT
FOR ICE JAM FLOODING THROUGH THE LONGER TERM. THE RIVERS WILL NEED
TO BE MONITORED CLOSELY AS WE HEAD THROUGH SPRING.

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

THE NEXT WINTER/SPRING FLOOD POTENTIAL OUTLOOK WILL BE ISSUED BY
NWS CARIBOU ON THURSDAY, MARCH 20, 2014, WITH AN INTERMEDIATE
UPDATE ISSUED ON THURSDAY, MARCH 13, 2014. 

$$

HASTINGS