Flood Potential Outlook
Issued by NWS St. Louis, MO

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FGUS73 KLSX 262146
ESFLSX
ILC001-009-013-027-051-149-MOC051-053-071-073-099-111-113-127-
137-151-163-173-183-189-221-272359-

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE ST. LOUIS MO
440 PM CDT FRI SEP 26 2014

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:  9/29/2014 - 12/28/2014

                                       :    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
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:Dardenne Creek
St. Peters          18.0   20.0   23.0 :  53   36   40   27   14   10
:Mississippi River
Canton LD20         14.0   20.0   25.0 :   7    6   <5   <5   <5   <5
Quincy              17.0   18.0   22.5 :   7    6    6   <5   <5   <5
Hannibal            16.0   22.0   24.0 :   9    7   <5   <5   <5   <5
Saverton LD22       16.0   20.0   22.0 :   7    6   <5   <5   <5   <5
Louisiana           15.0   20.0   25.0 :  12   12   <5   <5   <5   <5
Clarksville LD24    25.0   31.0   33.0 :  12   13   <5   <5   <5   <5
Winfield LD25       26.0   30.0   34.0 :   9    9   <5   <5   <5   <5
:North Fabius River
Ewing               11.0   14.0   18.0 :  37   24   21   13   <5   <5
:Middle Fabius River
Ewing               12.0   17.0   19.5 :  37   23   18    7   <5   <5
:South Fabius River
Taylor               9.5   14.0   19.0 :  39   29   14   10   <5   <5
:North River
Palmyra             13.0   16.0   22.0 :  32   24   20   13   <5   <5
:Mid Fork Salt River
Holliday            17.0   22.0   26.0 :  21   20   <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 :  37   20   15    7   <5   <5
Old Monroe          24.0   27.0   30.0 :  12    9    6    7   <5   <5
:Meramec River
Steelville          12.0   20.0   25.0 :   7   18   <5   <5   <5   <5
Sullivan            11.0   20.0   29.0 :  18   27   <5    6   <5   <5
:Bourbeuse River
Union               15.0   22.0   26.0 :  12   18   <5   <5   <5   <5
:Meramec River
Pacific             15.0   23.0   27.0 :   7   20   <5   <5   <5   <5
:Big River
Byrnesville         16.0   20.0   28.0 :  26   27   10   13   <5   <5
:Meramec River
Eureka              18.0   25.0   30.0 :   9   21   <5    7   <5    6
:Kaskaskia River
Carlyle TW         423.5  431.0  435.0 :  23   12   <5   <5   <5   <5
Vandalia            18.0   24.0   26.0 :  46   35   14   17   <5   <5
:La Moine River
Ripley              22.0   23.0   27.0 :  32   18   25   16    7   <5
:Moreau River
Jefferson City      17.0   25.0   29.0 :  28   40   11   14   <5    7
:Maries River
Westphalia          10.0   15.0   20.0 :  23   19   <5    8   <5   <5
:Gasconade River
Rich Fountain       20.0   25.0   30.0 :  <5   15   <5    5   <5   <5

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: 9/29/2014 - 12/28/2014
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Dardenne Creek
St. Peters            8.7   10.8   14.5   18.8   21.8   23.9   24.4
:Mississippi River
Canton LD20           8.3    8.3    8.3    8.7   10.2   12.9   15.1
Quincy               12.7   12.7   12.7   12.8   14.1   16.1   18.8
Hannibal             12.0   12.0   12.0   12.4   14.1   16.1   18.3
Saverton LD22         9.1    9.1    9.1    9.7   12.4   15.6   18.3
Louisiana            12.1   12.1   12.1   12.1   13.3   16.2   18.6
Clarksville LD24     19.5   19.5   19.6   20.0   22.9   26.4   29.2
Winfield LD25        19.6   19.6   19.6   20.1   23.0   26.5   29.2
:North Fabius River
Ewing                 4.1    4.6    7.1    8.8   13.9   16.9   17.8
:Middle Fabius River
Ewing                 3.5    3.9    6.6   10.0   15.0   19.0   19.4
:South Fabius River
Taylor                2.4    3.2    5.7    8.0   11.6   14.8   17.1
:North River
Palmyra               5.6    6.2    8.0    9.7   14.8   19.5   20.6
:Mid Fork Salt River
Holliday              4.5    5.6    8.0   11.8   16.7   18.9   21.2
:Salt River
New London            2.5    4.6    5.7    7.4    9.3   12.5   15.2
:Cuivre River
Troy                  7.0    8.8   13.5   18.4   24.1   26.3   28.6
Old Monroe           15.0   15.0   15.1   16.7   20.5   24.4   28.3
:Meramec River
Steelville            1.6    1.7    2.0    2.5    5.8   11.1   12.8
Sullivan              2.0    2.3    2.9    3.6    8.9   14.8   18.9
:Bourbeuse River
Union                 1.1    1.3    1.6    6.1   13.6   17.0   20.5
:Meramec River
Pacific              -2.0   -1.7   -0.5    2.3    9.1   14.0   20.6
:Big River
Byrnesville           2.8    3.3    4.2    6.8   16.3   20.3   23.9
:Meramec River
Eureka                2.0    2.2    2.6    4.7   13.2   18.2   28.8
:Kaskaskia River
Carlyle TW          418.4  418.6  418.8  420.4  423.2  424.7  425.5
Vandalia             10.4   10.8   12.5   17.5   22.5   25.6   25.9
:La Moine River
Ripley                5.3    8.9   11.8   17.2   23.2   25.4   28.8

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: 9/29/2014 - 12/28/2014
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Dardenne Creek
St. Peters            3.1    3.0    3.0    3.0    2.9    2.8    2.8
:Mississippi River
Canton LD20           4.5    3.9    3.5    3.1    2.8    2.6    2.5
Quincy               11.8   11.5   11.2   10.9   10.9   10.9   10.9
Hannibal             10.3   10.0    9.9    9.8    9.7    9.7    9.6
Saverton LD22         6.0    5.3    4.9    4.6    4.3    4.1    4.1
Louisiana            11.9   11.9   11.9   11.8   11.8   11.8   11.8
Clarksville LD24     16.0   15.1   14.6   14.1   13.8   13.5   13.5
Winfield LD25        15.8   14.9   14.4   14.0   13.6   13.4   13.3
:North Fabius River
Ewing                 3.2    3.2    3.1    3.0    2.9    2.9    2.9
:Middle Fabius River
Ewing                 3.0    3.0    2.9    2.9    2.9    2.9    2.9
:South Fabius River
Taylor                1.6    1.5    1.4    1.4    1.3    1.3    1.2
:North River
Palmyra               5.3    5.3    5.2    5.2    5.1    5.1    5.1
:Mid Fork Salt River
Holliday              4.2    4.2    4.1    4.1    4.1    4.1    4.1
:Salt River
New London            5.2    4.8    4.3    3.2    2.0    2.0    2.0
:Cuivre River
Troy                  4.9    4.9    4.8    4.8    4.7    4.7    4.7
Old Monroe           11.8   10.7   10.1    9.5    9.4    9.4    9.4
:Meramec River
Steelville            1.4    1.4    1.4    1.4    1.3    1.3    1.3
Sullivan              1.7    1.7    1.6    1.6    1.5    1.4    1.3
:Bourbeuse River
Union                 0.8    0.8    0.7    0.7    0.6    0.5    0.5
:Meramec River
Pacific              -2.1   -2.1   -2.1   -2.1   -2.1   -2.1   -2.1
:Big River
Byrnesville           1.4    1.3    1.2    1.1    1.0    0.8    0.7
:Meramec River
Eureka                1.7    1.7    1.7    1.6    1.6    1.5    1.5
:Kaskaskia River
Carlyle TW          411.1  411.1  411.1  411.1  411.1  411.1  411.1
Vandalia              2.3    2.2    2.2    2.1    2.1    2.1    2.0
:La Moine River
Ripley                4.9    4.8    4.5    4.3    4.3    4.2    4.2

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 toward the end next month.

$$

Fuchs









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