Flood Potential Outlook
Issued by NWS La Crosse, WI

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000
FGUS73 KARX 051530
ESFARX
IAC005-037-043-065-067-089-131-191-MNC039-045-055-099-109-157-169-
WIC001-011-019-023-043-053-057-063-081-103-119-121-123-131800-

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE LA CROSSE WI
930 AM CST THU MAR 5 2015

     ...SECOND SPRING HYDROLOGIC SUMMARY AND OUTLOOK...

THE FOLLOWING INFORMATION IS THE SECOND OF TWO PLANNED HYDROLOGIC
OUTLOOKS PROVIDING SPRING SNOWMELT AND FLOOD POTENTIAL INFORMATION
AS WELL AS CLIMATOLOGICAL INFORMATION FOR THIS COMING SPRING. THIS
OUTLOOK CONTAINS INFORMATION WHICH WAS COLLECTED FROM A NUMBER OF
SOURCES...INCLUDING THE UNITED STATES GEOLOGICAL SURVEY /USGS/...
US ARMY CORPS OF ENGINEERS /USACE/...MIDWEST REGIONAL CLIMATE CENTER
/MRCC/...AND THE NATIONAL OPERATIONAL REMOTE SENSING CENTER /NOHRSC/.

THE OUTLOOK THAT FOLLOWS BELOW IS A SUMMARY OF THE PAST AND PRESENT
BASIN CONDITIONS FOR PORTIONS OF SOUTHEAST MINNESOTA...NORTHEAST
IOWA...SOUTHEAST MINNESOTA...AND SOUTHWEST INTO CENTRAL WISCONSIN.

*** FLOOD POTENTIAL HIGHLIGHTS ***

OVERALL...NOT MUCH HAS CHANGED FROM THE FIRST OUTLOOK ISSUED TWO
WEEKS AGO. THE FLOOD POTENTIAL FOR THIS SPRING LOOKS TO BE BELOW
NORMAL AS COMPARED TO A TYPICAL YEAR.

THE WIDESPREAD LACK OF WINTER PRECIPITATION HAS CONTINUED...AND
CONTINUES TO BE WELL BELOW WHAT WE MIGHT NORMALLY SEE FOR THIS
TIME OF YEAR. THIS CONTINUES TO POINT TO A VERY LOW LIKELIHOOD OF
ANY SIGNIFICANT OR WIDESPREAD SPRING FLOODING FROM SNOWMELT RUNOFF
AT THIS TIME.

ONE AREA THAT REMAINS SOMEWHAT OF A CONCERN CONTINUES TO BE THE
AMOUNT AND THICKNESS OF ICE IN AREA CREEKS AND RIVERS. THE RECENT
COLD HAS HELPED TO THICKEN THE ICE. WITH WARMER TEMPERATURES EXPECTED
THIS WEEKEND AND THROUGH NEXT WEEK...RUNOFF MAY BE SUFFICIENT TO
RAISE WATER LEVELS ENOUGH TO BREAK THIS ICE UP ON SOME WATERWAYS.
AS THIS OCCURS...ICE JAMS ARE A DEFINITE POSSIBILITY...ESPECIALLY IN
TYPICAL PROBLEM SPOTS SUCH AS NEAR BRIDGES AND OTHER CONSTRICTIONS
IN THE RIVER...OR WHERE THE RIVER MAKES SHARP TURNS OR MEANDERS.
LARGE CHUNKS OF ICE MOVING DOWNSTREAM COULD GET HUNG UP IN THESE
AREAS...LEADING TO JAMS AND POTENTIAL FLOODING. IF ICE FLOES OR
ANY JAMMING IS OBSERVED...BE SURE TO REPORT THIS INFORMATION TO
LOCAL OFFICIALS OR THE NATIONAL WEATHER SERVICE.


IN TABLE 1 BELOW...THE CURRENT /CS/ AND HISTORICAL /HS/ /OR NORMAL/
PROBABILITIES OF EXCEEDING MINOR...MODERATE...AND MAJOR FLOOD STAGES
ARE LISTED FOR THE VALID TIME PERIOD.

CS VALUES INDICATE THE PROBABILITY OF REACHING A FLOOD CATEGORY
BASED ON CURRENT CONDITIONS.

HS VALUES INDICATE THE PROBABILITY OF REACHING A FLOOD CATEGORY
BASED ON HISTORICAL OR NORMAL CONDITIONS.

WHEN THE VALUE OF CS IS GREATER THAN HS...THE PROBABILITY OF
EXCEEDING THAT LEVEL IS HIGHER THAN NORMAL. WHEN THE VALUE OF CS IS
LESS THAN HS...THE PROBABILITY OF EXCEEDING THAT LEVEL IS LOWER THAN
NORMAL.

...TABLE 1--PROBABILITIES FOR MINOR...MODERATE AND MAJOR FLOODING...
                    VALID  PERIOD: 3/9/2015 - 6/7/2015

                                       :    CURRENT AND HISTORICAL
                                       :     CHANCES OF EXCEEDING
                                       :       FLOOD CATEGORIES
                                       :      AS A PERCENTAGE (%)
                      CATEGORICAL      :
                   FLOOD STAGES (FT)   :   MINOR    MODERATE   MAJOR
LOCATION           MINOR   MOD   MAJOR :  CS   HS   CS   HS   CS   HS
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:BLACK RIVER
NEILLSVILLE         18.0   20.0   22.0 :  <5   <5   <5   <5   <5   <5
BLK RVR FLS         47.0   51.0   55.0 :  29   61    9   21   <5   <5
GALESVILLE          12.0   13.0   15.0 :  26   58   15   38   <5   <5
:CEDAR RIVER
LANSING             18.0   20.0   22.0 :  <5   <5   <5   <5   <5   <5
AUSTIN              15.0   18.0   20.0 :  <5    9   <5   <5   <5   <5
CHARLES CTY         12.0   15.0   18.0 :   9   23   <5    9   <5    6
:TURTLE CREEK
AUSTIN              10.5   12.0   14.0 :   7   13   <5    6   <5   <5
:KICKAPOO RIVER
LA FARGE            12.0   13.0   14.0 :  <5   <5   <5   <5   <5   <5
VIOLA               14.0   17.0   20.0 :  10   32   <5   <5   <5   <5
READSTOWN           11.0   14.0   17.0 :  13   38   <5   <5   <5   <5
SLDRS GROVE         13.0   16.0   19.0 :   9   23   <5   <5   <5   <5
GAYS MILLS          13.0   15.0   17.0 :  23   47   <5    7   <5   <5
STEUBEN             12.0   13.0   15.0 :  16   38   <5   13   <5   <5
:MISSISSIPPI RIVER
LAKE CITY           16.0   18.0   20.0 :  <5   26   <5    7   <5   <5
WABASHA             12.0   14.0   16.0 :  18   56   <5   18   <5    7
ALMA                16.0   17.0   18.0 :  <5    7   <5   <5   <5   <5
DAM 5              660.0  662.0  665.0 :  <5   26   <5   10   <5    6
DAM 5A             656.0  659.0  661.0 :  <5   26   <5    7   <5   <5
WINONA              13.0   15.0   18.0 :  10   44   <5   18   <5    7
TREMPEALEAU        647.0  649.0  651.0 :   6   33   <5   13   <5    6
LA CRESCENT        641.0  643.0  645.0 :  <5   30   <5   10   <5    6
LA CROSSE           12.0   13.0   15.5 :   7   36   <5   18   <5    6
GENOA              631.0  634.0  636.0 :  13   46   <5   10   <5    6
LANSING             17.0   19.0   20.0 :  <5    9   <5    7   <5   <5
LYNXVILLE          625.0  628.0  631.0 :  <5   21   <5    7   <5   <5
MCGREGOR            16.0   19.0   22.0 :  15   50   <5   21   <5    7
GUTTENBERG          15.0   18.0   21.0 :  10   41   <5   12   <5   <5
:ROOT RIVER
HOUSTON             15.0   17.0   18.0 :   7   10   <5   <5   <5   <5
:SOUTH BRANCH ROOT RIVER
LANESBORO           12.0   16.0   18.0 :   9   15   <5   <5   <5   <5
:TREMPEALEAU RIVER
DODGE                9.0   11.0   12.0 :  41   61   <5   <5   <5   <5
:TURKEY RIVER
ELKADER             12.0   16.0   20.0 :  43   44   16   16    6   <5
GARBER              17.0   20.0   23.0 :  29   33   15   20   10    9
:UPPER IOWA RIVER
DECORAH             12.0   13.0   14.0 :  <5   <5   <5   <5   <5   <5
DORCHESTER          14.0   17.0   19.0 :  24   33    9    7   <5   <5
:WISCONSIN RIVER
MUSCODA              9.0   10.0   11.0 :  <5    8   <5    6   <5   <5
:ZUMBRO RIVER
ZUMBRO FLS          18.0   24.0   26.0 :  <5    6   <5   <5   <5   <5
:SOUTH FORK ZUMBRO RIVER
ROCHESTER           14.0   18.0   20.0 :  <5   <5   <5   <5   <5   <5

LEGEND
CS = CONDITIONAL SIMULATION (CURRENT OUTLOOK)
HS = HISTORICAL SIMULATION


*** CLIMATE INFORMATION ***

AUTUMN OF 2014 WAS SLIGHTLY WETTER...UP TO 2 INCHES ABOVE
NORMAL...TO THE NORTH OF INTERSTATE 94. BUT IT WAS DRIER ACROSS THE
REMAINDER OF THE HYDROLOGIC SERVICE AREA...UP TO 3 INCHES BELOW
NORMAL. THIS DRYNESS CONTINUED THROUGH THE 2014-15 METEOROLOGICAL
WINTER. AT THIS TIME...THE GREATEST PRECIPITATION DEFICITS OF 2 TO 4
INCHES BELOW NORMAL ARE FOUND IN SOUTHWEST AND WEST CENTRAL
WISCONSIN...INTO SOUTHEAST MINNESOTA. THESE AREAS ARE CURRENTLY
CLASSIFIED AS ABNORMALLY DRY /D0/ BY THE U.S. DROUGHT MONITOR.

DURING THE NEXT 2 WEEKS...THE CLIMATE PREDICTION CENTER /CPC/ IS
FORECASTING ABOVE-NORMAL TEMPERATURES FOR OUR AREA. THIS WILL HELP
ACCELERATE THE SNOW MELT ACROSS OUR AREA. THE CPC FORECAST ALSO
CALLS FOR BELOW-NORMAL CHANCES FOR PRECIPITATION. THE AMOUNT OF
WATER CONTAINED IN THE SNOW PACK IS ONLY BETWEEN 0.5 AND 1.5 INCHES
ACROSS THE AREA.  SO...WITH DRY SOIL CONDITIONS AND A BELOW-NORMAL
FORECAST OF PRECIPITATION...IT IS FELT THAT THE DRY SOILS CAN
EASILY ACCOMMODATE THIS MOISTURE.

THERE IS NO SHIFT IN THE CPC PRECIPITATION PROBABILITIES FOR THE
REMAINDER OF THE SPRING...KEEPING THE BELOW NORMAL PRECIPITATION
CHANCE ACROSS OUR REGION. AS A RESULT...THE SEASONAL DROUGHT OUTLOOK
IS FORECASTING THAT DROUGHT CONDITIONS ARE EXPECTED TO DEVELOP FOR
PARTS OF SOUTHERN MINNESOTA INTO THE SOUTHERN THIRD OF WISCONSIN.


*** FLOOD POTENTIAL SUMMARY ***

AS ALWAYS...THE FLOOD POTENTIAL ANALYSIS IS BASED ON CURRENT SOIL
AND SNOW CONDITIONS...COMBINED WITH A BROAD SPECTRUM OF POTENTIAL
SPRING WEATHER SCENARIOS REFLECTED IN THE CLIMATE RECORD FROM 1949
TO 2013. THE ANALYSIS BELOW IS VERY GENERAL. A MORE QUANTIFIED RISK
OF FLOODING WITH RESPECT TO CLIMATOLOGY IS AVAILABLE THROUGH WEB
GRAPHICS AND TABLES AT
HTTP://WATER.WEATHER.GOV/AHPS/LONG_RANGE.PHP?PERCENT=50

THE WINTER PRECIPITATION HAS BEEN BELOW NORMAL. SNOW WATER CONTENT
REMAINS QUITE LOW FOR THIS TIME OF YEAR...WITH MOST AREAS RANGING
BETWEEN 0.50 AND 1.50 INCHES. THE GREATEST WATER EQUIVALENT WAS SEEN
IN THE HEADWATERS OF THE BLACK RIVER WHERE AROUND 2.00 TO 2.25
INCHES IS SEEN. WATER CONTENT OF 3 TO 4 INCHES EXISTS IN THE FAR
NORTHERN HEADWATER AREAS OF THE WISCONSIN RIVER. OVERALL SOIL
CONDITIONS ARE DRY.

WINTER TEMPERATURES STARTED OUT ABOVE NORMAL IN DECEMBER AND EARLY
JANUARY...BUT SINCE THEN HAVE BEEN WELL BELOW NORMAL. THE MONTH OF
FEBRUARY WAS 11-13 DEGREES BELOW NORMAL. AS A RESULT...FROST DEPTH
HAS INCREASED OVER THE LAST 6 WEEKS. DEPTHS OF 2 TO 3 FEET ARE
INDICATED.

THE COLD TEMPERATURES HAVE ALSO INCREASED THE THICKNESS OF ICE IN
AREA CREEKS AND RIVERS.

STREAMFLOW CONDITIONS AS REPORTED BY THE USGS ARE NEAR NORMAL FOR
MINNESOTA...IOWA...AND SOUTHWEST WISCONSIN...BUT ARE SLIGHTLY ABOVE
NORMAL IN THE BLACK...TREMPEALEAU...AND WISCONSIN RIVER BASINS OF
NORTHERN AND CENTRAL WISCONSIN.

SO WHEN COMBINING ALL OF THE ABOVE FACTORS...THE OVERALL CHANCES FOR
FLOODING DUE STRICTLY TO SNOWMELT THIS SPRING ARE BELOW NORMAL. ANY
FLOOD RISK WE DO HAVE LOOKS TO BE FROM ANY ICE JAMMING OR IF WE SEE
SIGNIFICANT RAINFALL ON FROZEN SOILS. THE PRECIPITATION OUTLOOK FOR
THE NEXT MONTH SUGGESTS NO LARGE RAIN SYSTEMS.


IN TABLE 2 BELOW...THE 95 THROUGH 5 PERCENT COLUMNS INDICATE THE
PROBABILITY OF EXCEEDING THE LISTED STAGE LEVELS (FT) FOR THE VALID
TIME PERIOD. FOR EXAMPLE...FOR THE BLACK RIVER AT GALESVILLE...THERE
IS A 50% CHANCE THAT THE RIVER WILL RISE ABOVE 10.6 FEET...AND A 25%
CHANCE TO RISE ABOVE 12.3 FEET.

...TABLE 2--EXCEEDANCE PROBABILITIES...

                              CHANCE OF EXCEEDING STAGES
                                 AT SPECIFIC LOCATIONS
                          VALID  PERIOD: 3/9/2015 - 6/7/2015
LOCATION              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:BLACK RIVER
NEILLSVILLE           7.0    7.8    8.9   10.5   12.3   13.5   14.1
BLK RVR FLS          40.9   41.2   43.1   45.1   47.9   50.9   51.8
GALESVILLE            7.4    8.0    9.2   10.6   12.3   13.2   13.5
:CEDAR RIVER
LANSING              12.1   12.4   13.2   13.9   15.1   15.9   16.2
AUSTIN                5.8    6.0    7.0    8.0   10.0   11.2   11.9
CHARLES CTY           4.9    5.3    6.3    7.5    9.2   12.2   14.6
:TURTLE CREEK
AUSTIN                4.1    4.5    5.3    6.2    7.3    9.1   11.3
:KICKAPOO RIVER
LA FARGE              4.4    4.9    5.8    6.7    8.5    9.8   10.4
VIOLA                10.1   10.6   11.3   12.2   13.4   14.3   14.7
READSTOWN             5.8    6.4    7.4    8.6   10.5   11.7   12.0
SLDRS GROVE           8.2    8.7    9.7   10.9   12.1   13.1   13.7
GAYS MILLS            8.7    9.2   10.2   11.4   12.9   13.7   14.1
STEUBEN               8.3    8.8    9.8   10.9   11.7   12.5   12.7
:MISSISSIPPI RIVER
LAKE CITY             8.0    8.4   10.0   11.2   13.0   15.2   15.7
WABASHA               8.1    8.4    9.3   10.0   11.6   12.9   13.3
ALMA                  5.8    6.1    7.2    8.2    9.9   12.0   12.5
DAM 5               652.3  652.5  653.7  654.8  656.7  659.3  659.7
DAM 5A              647.0  647.4  649.3  650.3  652.1  655.0  655.6
WINONA                6.2    6.5    7.7    8.8   10.6   13.5   14.0
TREMPEALEAU         641.0  641.2  642.3  643.2  644.5  646.9  647.3
LA CRESCENT         633.7  634.2  635.4  636.6  638.4  640.4  641.0
LA CROSSE             6.2    6.3    7.0    8.2   10.1   11.8   12.3
GENOA               624.3  624.7  626.2  627.6  629.5  631.3  631.9
LANSING               8.5    8.5    8.9    9.8   11.2   13.1   14.0
LYNXVILLE           616.4  616.7  618.2  619.4  621.2  623.4  624.2
MCGREGOR              9.5   10.2   11.4   12.9   14.7   16.9   18.3
GUTTENBERG            8.6    9.3   10.5   11.8   13.3   15.2   16.3
:ROOT RIVER
HOUSTON               6.0    7.0    8.2    9.4   11.7   14.9   15.6
:SOUTH BRANCH ROOT RIVER
LANESBORO             3.6    4.2    5.3    6.6    8.8   11.9   15.4
:TREMPEALEAU RIVER
DODGE                 7.5    7.8    8.5    8.9    9.4   10.2   10.8
:TURKEY RIVER
ELKADER               7.4    8.0    9.1   11.6   14.7   16.8   22.2
GARBER                9.0    9.8   11.6   14.3   18.0   24.1   27.6
:UPPER IOWA RIVER
DECORAH               3.8    4.2    4.6    5.6    7.4    8.8    9.7
DORCHESTER            9.4    9.8   10.5   11.9   14.1   17.6   19.7
:WISCONSIN RIVER
MUSCODA               3.4    3.5    4.0    6.1    7.5    8.0    8.6
:ZUMBRO RIVER
ZUMBRO FLS            7.1    7.6    8.3   10.3   11.5   13.5   17.0
:SOUTH FORK ZUMBRO RIVER
ROCHESTER             4.4    4.7    5.0    6.2    7.2    8.3   13.8


THESE LONG-RANGE PROBABILISTIC OUTLOOKS CONTAIN FORECAST VALUES THAT
ARE CALCULATED USING MULTIPLE SEASON SCENARIOS FROM 30 OR MORE YEARS
OF CLIMATOLOGICAL DATA...INCLUDING CURRENT CONDITIONS OF THE
RIVER...SOIL MOISTURE...SNOW COVER...AND 30 TO 90 DAY LONG-RANGE
OUTLOOKS OF TEMPERATURE AND PRECIPITATION. BY PROVIDING A RANGE OF
PROBABILITIES...THE LEVEL OF RISK ASSOCIATED WITH LONG-RANGE
PLANNING DECISIONS CAN BE DETERMINED. THESE PROBABILISTIC FORECASTS
ARE PART OF THE NATIONAL WEATHER SERVICE/S ADVANCED HYDROLOGIC
PREDICTION SERVICE /AHPS/.

ALL OF THIS INFORMATION IS ALSO AVAILABLE IN GRAPHICAL FORMAT ON THE
INTERNET AT:  HTTP://WWW.WEATHER.GOV/LACROSSE

ADDITIONAL INFORMATION IS ALSO AVAILABLE ON THE NORTH CENTRAL RIVER
FORECAST CENTER WEBSITE AT:  HTTP://WWW.CRH.NOAA.GOV/NCRFC

THE NEXT OUTLOOK WILL BE ISSUED IN LATE MARCH.

$$

WELVAERT/BOYNE



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