FGUS73 KILX 261755

ESFILX

ILC009-017-025-033-057-079-095-101-113-123-125-129-137-143-147-

155-159-167-169-179-183-203-271800-



PROBABILISTIC HYDROLOGIC OUTLOOK

NATIONAL WEATHER SERVICE Lincoln IL

1253 PM CDT Thu Jun 26 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:  06/30/2025 - 09/28/2025



                                       :    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

--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---

:Illinois River

Henry               23.0   24.0   31.0 :  12   18    9   13   <5   <5

Peoria              18.0   22.0   28.0 :  18   26   <5    8   <5   <5

Peoria L/D         447.0  449.0  455.0 :  11   17    5    8   <5   <5

Havana              14.0   17.0   23.0 :  33   41   17   21   <5   <5

Beardstown          14.0   18.0   28.0 :  24   35    9   17   <5   <5

:Mackinaw River

Congerville         13.0   14.0   20.0 :  10    9    9    7   <5   <5

:Spoon River

London Mills        15.0   21.0   24.0 :  15   17   <5    5   <5   <5

Seville             22.0   25.0   30.0 :  10   11    6    7   <5   <5

:Sangamon River

Monticello          13.0   17.0   20.0 :  19   15   <5   <5   <5   <5

Riverton            23.0   26.0   29.0 :  <5   <5   <5   <5   <5   <5

Petersburg          23.0   24.0   33.0 :  <5   <5   <5   <5   <5   <5

:Salt Creek

Greenview           16.0   17.0   20.0 :   5    7   <5    5   <5   <5

:Sangamon River

Oakford            471.0  472.9  478.5 :   5    8   <5   <5   <5   <5

Chandlerville      456.6  459.0  462.0 :   8   14   <5   <5   <5   <5

:Embarras River

Lawrenceville       30.0   37.0   41.0 :  21   14   <5   <5   <5   <5

Ste. Marie          19.0   20.0   27.0 :   8    5    6   <5   <5   <5

:Little Wabash River

Clay City           18.0   22.0   25.0 :  38   32   <5    7   <5   <5

:Vermilion River

Danville            18.0   22.0   28.0 :   7   <5   <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: 06/30/2025 - 09/28/2025

Location              95%    90%    75%    50%    25%    10%     5%

--------            ------ ------ ------ ------ ------ ------ ------

:Illinois River

Henry                15.0   15.1   16.1   16.5   20.2   23.2   25.7

Peoria               12.1   12.2   12.8   13.1   15.6   19.7   21.9

Peoria L/D          432.4  433.0  435.5  436.1  443.1  447.1  449.1

Havana                5.6    6.2    8.7   10.8   15.1   18.4   20.5

Beardstown            9.8   10.0   10.7   11.1   12.9   17.7   20.1

:Mackinaw River

Congerville           2.2    2.2    2.2    3.5    6.0   13.4   15.9

:Spoon River

London Mills          2.1    2.9    4.7    6.1   10.7   16.3   20.5

Seville               5.2    5.9    8.2   10.0   14.5   22.7   26.3

:Sangamon River

Monticello            5.5    5.5    6.7    7.8   11.6   14.0   15.8

Riverton              4.3    4.4    5.3    8.2   13.2   16.7   18.4

Petersburg            5.5    5.5    6.0    6.8   10.9   12.6   18.0

:Salt Creek

Greenview             1.7    2.2    3.0    4.8    6.7   14.0   16.8

:Sangamon River

Oakford             457.3  457.4  458.0  460.0  462.8  468.6  471.2

Chandlerville       444.6  444.7  445.2  447.1  450.2  456.0  458.2

:Embarras River

Lawrenceville        19.3   20.3   22.0   24.8   28.8   33.6   34.1

Ste. Marie            3.2    3.9    5.8    8.6   13.1   17.7   20.5

:Little Wabash River

Clay City             7.1    8.4   11.3   16.4   19.7   20.7   21.9

:Vermilion River

Danville              4.5    4.8    6.3    7.9   10.6   14.8   19.8



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: 06/30/2025 - 09/28/2025

Location              95%    90%    75%    50%    25%    10%     5%

--------            ------ ------ ------ ------ ------ ------ ------

:Illinois River

Henry                 2.7    2.5    2.1    1.7    1.5    1.2    1.1

Peoria                2.9    2.7    2.2    1.8    1.5    1.3    1.2

Peoria L/D            3.0    2.8    2.2    1.8    1.5    1.3    1.2

Havana                3.8    3.4    2.5    2.1    1.7    1.5    1.4

Beardstown            5.4    4.2    3.2    2.4    2.0    1.7    1.6

:Mackinaw River

Congerville           0.1    0.1    0.1    0.0    0.0    0.0    0.0

:Spoon River

London Mills          0.1    0.1    0.0    0.0    0.0    0.0    0.0

Seville               0.1    0.1    0.1    0.0    0.0    0.0    0.0

:Sangamon River

Monticello            0.1    0.1    0.0    0.0    0.0    0.0    0.0

Riverton              0.4    0.3    0.1    0.1    0.0    0.0    0.0

Petersburg            0.5    0.3    0.2    0.1    0.1    0.1    0.1

:Salt Creek

Greenview             0.3    0.2    0.1    0.1    0.0    0.0    0.0

:Sangamon River

Oakford               0.9    0.6    0.3    0.2    0.1    0.1    0.1

Chandlerville         0.9    0.6    0.4    0.2    0.2    0.1    0.1

:Embarras River

Lawrenceville        17.4   17.3   17.1   16.9   16.8   16.7   16.7

Ste. Marie            2.2    2.0    1.8    1.6    1.5    1.4    1.3

:Little Wabash River

Clay City             4.1    3.8    3.6    2.8    2.8    2.8    2.8

:Vermilion River

Danville              3.0    2.8    2.7    2.5    2.4    2.3    2.3



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 NWS-National Water Prediction Service (NWPS).



Visit our web site weather.gov/ilx for more weather and water

information.



The next outlook will be issued the last week of July.



$$



DRH





