600   
FGUS73 KLSX 011301  
ESFLSX  
ILC001-009-013-027-051-149-MOC051-053-071-073-099-111-113-127-  
137-151-163-173-183-189-221-DDHHMM-  
  
PROBABILISTIC HYDROLOGIC OUTLOOK  
NATIONAL WEATHER SERVICE ST. LOUIS MO  
755 AM CDT TUE APR 01 2025  
  
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 MORE 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:  03/31/2025 - 06/29/2025  
  
                                       :    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  
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---  
:MISSISSIPPI RIVER  
CANTON              15.0   20.0   25.0 :  37   64    7   15   <5   <5  
LAGRANGE            17.0   23.0   25.0 :  30   54   <5   10   <5   <5  
QUINCY              19.0   22.0   26.0 :  32   56   13   30   <5   10  
LOCK & DAM 21       18.0   21.0   25.0 :  31   56   13   26   <5   10  
HANNIBAL            17.0   22.0   24.0 :  47   64    8   14    7   10  
SAVERTON            16.0   20.0   24.0 :  50   67   14   40    7   11  
LOUISIANA           15.0   20.0   25.0 :  69   76   13   35   <5    8  
CLARKSVILLE         25.0   31.0   33.0 :  70   76   13   28    8   13  
WINFIELD            26.0   30.0   34.0 :  56   71   15   43    6   10  
GRAFTON             20.0   24.0   29.0 :  41   67   12   19    7   10  
MEL PRICE LD        21.0   29.0   34.0 :  50   80   20   25   <5   11  
ST. LOUIS           30.0   35.0   40.0 :  39   60   22   34    7   17  
HERCULANEUM         26.0   32.0   37.0 :  48   63   22   36   10   18  
CHESTER             27.0   35.0   40.0 :  59   81   26   43   16   25  
:NORTH FABIUS RIVER  
EWING               11.0   17.0   20.0 :  59   56   17   15   11   11  
:MIDDLE FABIUS RIVER  
EWING               12.0   17.0   20.0 :  46   50   16   17   10   12  
:SOUTH FABIUS RIVER  
TAYLOR              10.0   14.0   19.0 :  33   48   14   17    7    7  
:NORTH RIVER  
PALMYRA             13.0   16.0   22.0 :  25   28   10   12   <5   <5  
:MID FORK SALT RIVER  
HOLLIDAY            17.0   22.0   26.0 :  53   51   <5   <5   <5   <5  
:SALT RIVER  
NEW LONDON          19.0   25.0   27.0 :  <5   <5   <5   <5   <5   <5  
:CUIVRE RIVER  
TROY                21.0   25.0   29.0 :  55   53   21   18    8    8  
OLD MONROE          24.0   27.0   30.0 :  44   62   24   27    8   14  
:DARDENNE CREEK  
ST. PETERS          18.0   20.0   23.0 :  34   33   26   25    7    7  
:MERAMEC RIVER  
STEELVILLE          12.0   20.0   25.0 :  41   35   <5   <5   <5   <5  
SULLIVAN            11.0   20.0   29.0 :  62   59   13   13   <5   <5  
:BOURBEUSE RIVER  
UNION               15.0   22.0   26.0 :  51   47    9    9   <5   <5  
:MERAMEC RIVER  
PACIFIC             15.0   23.0   27.0 :  42   38    6    5   <5   <5  
:BIG RIVER  
BYRNESVILLE         16.0   20.0   28.0 :  46   44   21   20   <5   <5  
:MERAMEC RIVER  
EUREKA              19.0   26.0   31.0 :  40   38   14   17    5    5  
VALLEY PARK         18.0   21.0   27.0 :  46   48   33   34   13   22  
FENTON              23.0   29.0   32.0 :  44   50   14   22    9   11  
ARNOLD              24.0   35.0   38.0 :  59   81   19   28   15   20  
:KASKASKIA RIVER  
VANDALIA            18.0   24.0   26.0 :  72   75   28   31   18   19  
CARLYLE             16.5   23.0   27.0 :  53   72   <5   <5   <5   <5  
NEW ATHENS          79.0   82.0   85.0 :  39   43   36   40   27   25  
:LA MOINE RIVER  
RIPLEY              22.0   23.0   27.0 :  41   50   33   40   13   14  
:MOREAU RIVER  
JEFFERSON CITY      17.0   25.0   29.0 :  70   75   46   53   19   28  
:HINKSON CREEK  
COLUMBIA            15.0   18.0   20.0 :  55   56   25   27    9    9  
:MARIES RIVER  
WESTPHALIA          10.0   15.0   20.0 :  49   50   21   26   <5   <5  
:GASCONADE RIVER  
RICH FOUNTAIN       20.0   25.0   30.0 :  22   35   10   22    5    6  
:MISSOURI RIVER  
JEFFERSON CITY      23.0   25.0   30.0 :  43   68   26   54   16   28  
:OSAGE RIVER  
ST. THOMAS          23.0   30.0   35.0 :  <5   17   <5   <5   <5   <5  
MARI-OSA CAMPGROU   19.0   22.0   25.0 :  41   60   18   31   14   22  
:MISSOURI RIVER  
CHAMOIS             17.0   28.0   31.0 :  64   80   12   18   <5   10  
HERMANN             21.0   26.0   33.0 :  56   78   25   46   14   21  
WASHINGTON          20.0   28.0   31.0 :  49   70   19   21    6   19  
ST. CHARLES         25.0   30.0   36.0 :  48   72   22   27   <5   15  
  
LEGEND  
CS = CONDITIONAL SIMULATION (CURRENT OUTLOOK)  
HS = HISTORICAL SIMULATION  
FT = FEET  
  
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.  
   
..TABLE 2--EXCEEDANCE PROBABILITIES  
  
                               CHANCE OF EXCEEDING STAGES  
                                  AT SPECIFIC LOCATIONS  
                          VALID PERIOD: 03/31/2025 - 06/29/2025  
LOCATION              95%    90%    75%    50%    25%    10%     5%  
--------            ------ ------ ------ ------ ------ ------ ------  
:MISSISSIPPI RIVER  
CANTON               10.1   10.6   12.2   14.3   16.4   19.3   21.2  
LAGRANGE             11.0   11.5   13.1   15.2   17.2   20.2   22.1  
QUINCY               13.5   14.0   15.2   17.2   19.8   23.1   25.5  
LOCK & DAM 21        11.3   12.0   13.6   16.1   18.5   21.9   24.5  
HANNIBAL             13.3   13.7   14.8   16.5   18.6   21.5   24.3  
SAVERTON             11.1   11.8   13.5   16.1   18.6   22.1   24.8  
LOUISIANA            12.3   12.7   14.1   16.2   18.8   21.6   23.8  
CLARKSVILLE          21.4   22.1   23.9   26.4   29.4   32.2   34.3  
WINFIELD             21.6   22.3   24.1   26.4   29.5   32.2   34.2  
GRAFTON              15.9   16.0   16.7   19.4   21.0   24.1   30.2  
MEL PRICE LD         13.6   14.7   17.4   21.0   25.6   31.5   32.9  
ST. LOUIS            16.6   17.4   22.1   26.7   32.9   39.5   41.0  
HERCULANEUM          14.7   15.5   20.1   24.6   30.6   37.2   38.7  
CHESTER              17.9   19.6   24.3   28.4   36.0   43.1   43.4  
:NORTH FABIUS RIVER  
EWING                 7.5    7.6    8.7   11.8   15.4   20.5   24.2  
:MIDDLE FABIUS RIVER  
EWING                 5.7    6.2    7.8   11.2   16.0   20.2   22.9  
:SOUTH FABIUS RIVER  
TAYLOR                4.0    5.0    6.1    8.6   12.1   17.0   19.8  
:NORTH RIVER  
PALMYRA               5.8    6.2    7.3    9.4   13.0   16.0   18.1  
:MID FORK SALT RIVER  
HOLLIDAY             11.0   11.3   14.2   17.2   19.2   20.7   21.6  
:SALT RIVER  
NEW LONDON            8.3    8.7    9.3    9.9   11.5   13.1   13.8  
:CUIVRE RIVER  
TROY                 12.7   13.1   16.4   21.7   24.8   28.6   29.5  
OLD MONROE           17.9   18.4   20.0   23.4   26.6   29.1   30.6  
:DARDENNE CREEK  
ST. PETERS            7.1    7.8    9.8   13.4   20.4   22.4   23.8  
:MERAMEC RIVER  
STEELVILLE            3.8    5.1    7.0   10.1   14.3   16.5   19.4  
SULLIVAN              6.8    7.5    9.2   12.9   17.4   20.7   23.7  
:BOURBEUSE RIVER  
UNION                 7.1    8.8   11.6   15.1   19.5   21.5   24.9  
:MERAMEC RIVER  
PACIFIC               3.9    5.7    9.8   14.1   17.3   21.8   23.7  
:BIG RIVER  
BYRNESVILLE           6.4    7.2   11.6   15.7   19.5   22.3   23.4  
:MERAMEC RIVER  
EUREKA                7.7    9.7   13.3   16.8   22.4   28.8   31.2  
VALLEY PARK          12.0   13.0   13.6   16.4   23.7   29.2   39.4  
FENTON               16.5   17.9   18.7   20.8   27.1   29.9   38.7  
ARNOLD               16.3   16.4   22.2   27.1   31.9   39.3   41.4  
:KASKASKIA RIVER  
VANDALIA             16.9   17.0   17.9   22.4   25.2   27.8   29.2  
CARLYLE              13.6   13.7   14.7   16.7   19.4   21.7   22.1  
NEW ATHENS           72.2   72.2   73.0   76.4   85.6   90.2   92.7  
:LA MOINE RIVER  
RIPLEY               11.5   12.4   15.9   20.2   25.2   27.8   28.5  
:MISSOURI RIVER  
JEFFERSON CITY       11.4   12.9   17.1   21.0   25.3   35.0   35.5  
:OSAGE RIVER  
ST. THOMAS            6.7    8.5   10.4   12.2   15.3   21.3   22.7  
MARI-OSA CAMPGROU     8.3   10.9   13.4   17.4   20.5   25.7   28.9  
:MISSOURI RIVER  
CHAMOIS               8.8   10.3   13.8   19.1   22.4   29.0   29.8  
HERMANN              10.9   13.1   16.4   22.6   26.3   34.2   34.7  
WASHINGTON            8.2   11.3   14.0   19.8   23.1   30.5   31.6  
ST. CHARLES          14.4   18.1   20.1   24.5   27.5   34.8   35.5  
  
IN TABLE 3 BELOW...THE 95 THROUGH 5 PERCENT COLUMNS INDICATE THE  
PROBABILITY OF FALLING BELOW THE LISTED STAGE LEVELS (FT) FOR THE  
VALID TIME PERIOD.  
   
..TABLE 3--NONEXCEEDANCE PROBABILITIES  
  
                            CHANCE OF FALLING BELOW STAGES  
                                 AT SPECIFIC LOCATIONS  
                          VALID PERIOD: 03/31/2025 - 06/29/2025  
LOCATION              95%    90%    75%    50%    25%    10%     5%  
--------            ------ ------ ------ ------ ------ ------ ------  
:MISSISSIPPI RIVER  
CANTON               91.9   91.4   89.2   68.1   49.3   39.6   36.6  
QUINCY               93.6   93.2   89.9   68.3   49.7   39.8   36.7  
LOCK & DAM 21        93.6   93.2   89.9   68.3   49.7   39.8   36.7  
HANNIBAL             95.5   95.1   90.2   68.5   49.9   39.9   36.8  
SAVERTON             94.4   94.1   90.2   68.8   50.0   40.0   36.8  
LOUISIANA           103.4  103.2   93.1   70.2   51.7   40.5   38.3  
CLARKSVILLE         103.6  103.4   93.3   70.5   51.8   40.5   38.3  
WINFIELD            105.5  105.3   93.4   71.0   51.9   40.6   38.4  
ST. LOUIS           172.9  170.7  169.7  154.1  123.9  102.0   92.2  
CHESTER             179.2  178.0  176.5  165.5  128.6  104.2   94.9  
:NORTH FABIUS RIVER  
EWING                 0.1    0.0    0.0    0.0    0.0    0.0    0.0  
:MIDDLE FABIUS RIVER  
EWING                 0.0    0.0    0.0    0.0    0.0    0.0    0.0  
:SOUTH FABIUS RIVER  
TAYLOR                0.0    0.0    0.0    0.0    0.0    0.0    0.0  
:NORTH RIVER  
PALMYRA               0.0    0.0    0.0    0.0    0.0    0.0    0.0  
:MID FORK SALT RIVER  
HOLLIDAY              0.0    0.0    0.0    0.0    0.0    0.0    0.0  
:SALT RIVER  
NEW LONDON            1.8    1.8    1.3    0.8    0.1    0.1    0.1  
:CUIVRE RIVER  
TROY                  0.2    0.1    0.1    0.0    0.0    0.0    0.0  
OLD MONROE            0.3    0.2    0.1    0.1    0.0    0.0    0.0  
:DARDENNE CREEK  
ST. PETERS            0.0    0.0    0.0    0.0    0.0    0.0    0.0  
:MERAMEC RIVER  
STEELVILLE            0.4    0.4    0.3    0.2    0.2    0.1    0.1  
SULLIVAN              0.8    0.7    0.6    0.5    0.4    0.3    0.3  
:BOURBEUSE RIVER  
UNION                 0.2    0.2    0.2    0.1    0.1    0.1    0.1  
:MERAMEC RIVER  
PACIFIC               1.4    1.2    0.9    0.7    0.6    0.5    0.4  
:BIG RIVER  
BYRNESVILLE           0.5    0.4    0.3    0.2    0.2    0.1    0.1  
:MERAMEC RIVER  
EUREKA                2.0    1.7    1.3    1.0    0.8    0.7    0.6  
:KASKASKIA RIVER  
VANDALIA              1.2    1.1    0.2    0.1    0.1    0.1    0.0  
CARLYLE               2.5    2.5    2.1    0.1    0.1    0.1    0.1  
:LA MOINE RIVER  
RIPLEY                0.3    0.2    0.2    0.1    0.0    0.0    0.0  
:MISSOURI RIVER  
JEFFERSON CITY        3.8    3.8    3.8    3.8    3.8    3.6    3.2  
:OSAGE RIVER  
ST. THOMAS            3.8    3.6    2.8    2.6    2.4    2.4    2.0  
:MISSOURI RIVER  
CHAMOIS               1.0    1.0    1.0    1.0    1.0    0.6    0.1  
HERMANN               3.8    3.8    3.8    3.8    3.8    3.4    2.9  
WASHINGTON            1.9    1.9    1.9    1.9    1.9    1.6    1.1  
ST. CHARLES           8.5    8.5    8.5    8.5    8.5    8.5    7.9  
  
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.  
  
VISIT OUR WEB SITE WEATHER.GOV/LSX FOR MORE WEATHER AND WATER  
INFORMATION.  
  
THE NEXT OUTLOOK WILL BE ISSUED THE LAST WEEK OF APRIL.  
  
  
FUCHS  
 
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