Flood Potential Outlook
Issued by NWS Chicago, IL

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000
FGUS73 KLOT 131844
ESFLOT
ILC007-011-031-037-063-075-089-091-093-097-099-103-105-111-
141-197-201-INC073-089-111-127-141900

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE Chicago/Romeoville IL
1243 PM CST Tue Feb 13 2024

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:  02/19/2024 - 05/19/2024

                                       :    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
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:Pecatonica River
Shirland            12.0   14.0   15.5 :  27   37    5   17   <5   <5
:Rock River
Rockton             10.0   11.0   14.0 :  23   35   12   21   <5    8
Latham Park          9.0   11.0   13.5 :  25   36    9   13   <5    7
Rockford (Auburn     6.0    8.5   10.0 :   5   10   <5   <5   <5   <5
:Kishwaukee River
Belvidere            9.0   10.0   12.0 :   5   12   <5    7   <5   <5
:SB Kishwaukee River
DeKalb              10.0   11.0   12.5 :  <5   10   <5   <5   <5   <5
:Kishwaukee River
Perryville          12.0   18.0   22.0 :  28   40   <5   <5   <5   <5
:Rock River
Byron               13.0   14.0   16.0 :  12   15    7   13   <5    9
Dixon               16.0   18.0   20.0 :   7   16   <5    7   <5   <5
:North Branch Chicago River
Chicago (Pulaski    18.0   20.0   21.0 :  <5   <5   <5   <5   <5   <5
:Des Plaines River
Russell              7.0    9.0   10.0 :  33   41   <5    6   <5   <5
Gurnee               7.0    9.0   11.0 :  30   33   <5    8   <5   <5
Lincolnshire        12.5   14.0   15.5 :  16   17   <5    9   <5    6
Des Plaines         15.0   18.0   19.0 :  23   20    5    7   <5   <5
River Forest        16.0   17.5   18.5 :   6   <5   <5   <5   <5   <5
Riverside            7.5    8.0    9.0 :  17   22   11   13   <5   <5
Lemont              10.0   13.0   15.0 :  47   45   <5   <5   <5   <5
:WB Du Page River
Warrenville         11.5   14.5   17.5 :  12   19   <5   <5   <5   <5
:East Branch Du Page River
Bolingbrook         20.0   22.0   24.0 :  <5    7   <5   <5   <5   <5
:Du Page River
Plainfield          12.0   14.0   15.0 :  <5    5   <5   <5   <5   <5
Shorewood           15.5   17.5   19.5 :  30   33    9   12   <5   <5
:Fox River
Algonquin Lock &     9.5   10.5   12.0 :  50   43   18   24   <5   11
Montgomery          13.5   15.0   16.0 :  11   14   <5   <5   <5   <5
Dayton              12.0   14.0   24.0 :  41   46   16   18   <5   <5
:Kankakee River
Dunns Bridge        10.0   12.0   13.0 :  21   30   <5    7   <5    6
Shelby              10.5   11.5   12.5 :  42   52   20   25   11   16
Momence              5.0    6.5    9.0 :  28   31   12   12   <5   <5
:Iroquois River
Rensselaer          12.0   14.0   15.0 :  28   34    8   12    8    9
Foresman            18.0   22.0   24.0 :  34   39    5    6   <5   <5
Iroquois            18.0   24.0   25.0 :  69   73    6    7   <5    5
:Sugar Creek
Milford             18.0   22.0   26.0 :  50   51   12   16    5    5
:Iroquois River
Chebanse            16.0   18.0   20.0 :  18   16    8   11    7    9
:Kankakee River
Wilmington           6.5    8.0   10.0 :  19   19    8    9   <5   <5
:Mazon River
Coal City           12.0   16.0   19.0 :  20   23   <5   <5   <5   <5
:Vermilion River
Pontiac             14.0   15.0   18.0 :  14   14    9   10   <5   <5
Leonore             16.0   21.0   26.0 :  38   35   13   14   <5   <5
:Hart Ditch
Dyer                12.0   13.0   14.0 :  <5   <5   <5   <5   <5   <5
:Thorn Creek
Thornton             9.0   14.0   15.5 :  16   20   <5   <5   <5   <5
:Little Calumet River
Munster (Hohman A   12.0   14.0   17.0 :  48   53   15   22    7   12
South Holland       16.5   18.0   20.0 :  <5   <5   <5   <5   <5   <5
:Illinois River
Morris              16.0   18.0   22.0 :  35   38   22   26   14   13
Ottawa             463.0  467.0  471.0 :  38   39   17   18   <5    5
La Salle            20.0   27.0   31.0 :  77   73   20   22   <5    9

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: 02/19/2024 - 05/19/2024
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Pecatonica River
Shirland              7.3    7.8    9.0   10.8   12.1   13.0   14.0
:Rock River
Rockton               6.1    6.3    7.3    8.6    9.8   11.2   13.1
Latham Park           5.6    5.7    6.4    7.7    9.0   10.5   12.6
Rockford (Auburn      3.0    3.0    3.1    3.3    3.7    4.6    6.0
:Kishwaukee River
Belvidere             3.1    3.6    4.8    5.9    7.2    8.7    9.1
:SB Kishwaukee River
DeKalb                4.8    5.5    6.1    6.8    8.1    9.4    9.9
:Kishwaukee River
Perryville            8.1    8.6    9.7   10.7   12.2   13.4   14.7
:Rock River
Byron                 8.0    8.3    9.1   10.7   11.8   13.4   14.9
Dixon                10.3   10.5   11.1   12.4   13.4   14.8   16.6
:North Branch Chicago River
Chicago (Pulaski     12.5   13.1   14.0   14.8   15.5   17.0   17.7
:Des Plaines River
Russell               4.6    5.2    6.0    6.7    7.1    7.6    8.3
Gurnee                4.0    4.7    5.4    6.4    7.2    8.1    8.6
Lincolnshire          8.3    8.9    9.4   10.5   11.7   13.5   14.0
Des Plaines          10.0   11.2   12.1   13.6   14.9   16.9   18.2
River Forest          7.3    8.4    9.9   11.4   12.7   14.7   16.0
Riverside             4.0    4.5    5.3    6.3    7.0    8.1    8.8
Lemont                7.5    8.1    9.1    9.9   10.5   11.7   12.6
:WB Du Page River
Warrenville           8.9    9.1    9.6   10.4   11.2   11.6   11.9
:East Branch Du Page River
Bolingbrook          16.6   16.8   17.2   18.0   18.8   19.4   19.8
:Du Page River
Plainfield            8.2    8.2    8.9    9.9   10.5   11.3   11.8
Shorewood            11.7   12.0   12.7   13.9   15.3   16.7   17.3
:Fox River
Algonquin Lock &      7.2    7.7    8.3    9.5   10.2   11.2   11.6
Montgomery           12.1   12.3   12.6   12.9   13.2   13.5   13.6
Dayton                8.3    9.1    9.9   11.6   12.5   15.3   16.7
:Kankakee River
Dunns Bridge          6.1    7.1    7.9    8.7    9.8   10.8   11.2
Shelby                7.8    8.4    9.1   10.2   11.2   13.3   14.8
Momence               3.0    3.2    3.5    4.3    5.1    7.6    8.2
:Iroquois River
Rensselaer            7.6    8.5    9.6   11.0   12.2   13.6   18.3
Foresman             13.1   14.2   15.6   17.3   18.8   20.4   22.3
Iroquois             14.2   15.8   17.7   19.2   21.3   22.5   24.6
:Sugar Creek
Milford              12.0   13.3   16.3   18.0   19.8   22.9   26.1
:Iroquois River
Chebanse              8.3    9.4   11.0   12.6   15.2   16.9   20.2
:Kankakee River
Wilmington            3.3    3.6    4.2    5.1    6.0    7.8    8.7
:Mazon River
Coal City             4.5    5.4    7.6   10.0   11.2   13.6   13.9
:Vermilion River
Pontiac               5.2    6.2    7.7    9.8   11.7   14.6   17.5
Leonore               7.7    9.7   11.9   14.6   17.6   21.6   24.3
:Hart Ditch
Dyer                  3.7    4.1    4.9    5.7    6.7    7.8    8.3
:Thorn Creek
Thornton              4.6    5.2    6.3    7.4    8.7   10.0   11.3
:Little Calumet River
Munster (Hohman A     8.9    9.7   10.6   11.9   13.2   15.7   17.9
South Holland         9.0    9.8   11.1   12.2   13.8   14.8   15.3
:Illinois River
Morris                7.7    8.2   10.9   14.2   17.5   22.6   23.9
Ottawa              459.2  459.3  460.5  461.9  464.7  469.2  470.0
La Salle             15.5   16.0   20.2   23.4   25.8   30.1   30.9

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: 02/19/2024 - 05/19/2024
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Pecatonica River
Shirland              6.8    6.4    6.0    5.5    4.9    4.6    4.5
:Rock River
Rockton               5.9    5.5    5.3    4.6    4.0    3.6    3.3
Latham Park           5.4    5.2    5.1    4.8    4.5    4.3    4.1
Rockford (Auburn      3.0    2.9    2.9    2.8    2.6    2.4    2.4
:Kishwaukee River
Belvidere             2.0    1.9    1.8    1.6    1.4    1.3    1.2
:SB Kishwaukee River
DeKalb                3.4    3.3    3.3    3.2    3.2    3.1    3.1
:Kishwaukee River
Perryville            6.5    6.4    6.3    6.0    5.8    5.7    5.6
:Rock River
Byron                 7.4    7.3    7.0    6.6    6.0    5.6    5.5
Dixon                 9.7    9.5    9.3    8.9    8.4    8.0    7.9
:North Branch Chicago River
Chicago (Pulaski     11.1   11.1   11.0   10.9   10.9   10.8   10.7
:Des Plaines River
Russell               3.3    3.2    3.1    3.0    2.9    2.7    2.6
Gurnee                2.4    2.3    2.2    1.9    1.8    1.5    1.4
Lincolnshire          7.0    6.9    6.8    6.5    6.4    6.2    6.1
Des Plaines           8.7    8.7    8.6    8.3    8.2    8.0    7.9
River Forest          4.8    4.6    4.3    3.8    3.6    3.2    2.9
Riverside             2.6    2.5    2.4    2.2    2.0    1.9    1.8
Lemont                6.0    6.0    5.8    5.6    5.3    5.2    5.0
:WB Du Page River
Warrenville           7.7    7.6    7.6    7.5    7.5    7.4    7.4
:East Branch Du Page River
Bolingbrook          14.6   14.5   14.5   14.4   14.3   14.2   14.1
:Du Page River
Plainfield            6.8    6.8    6.8    6.7    6.6    6.6    6.6
Shorewood            10.4   10.4   10.3   10.2   10.1   10.1   10.1
:Fox River
Algonquin Lock &      6.2    5.9    5.6    5.4    5.0    4.8    4.5
Montgomery           11.7   11.7   11.5   11.3   11.2   11.1   11.0
Dayton                7.3    6.9    6.5    6.1    5.8    5.5    5.4
:Kankakee River
Dunns Bridge          4.5    4.3    4.0    3.7    3.5    3.2    3.0
Shelby                6.1    5.9    5.7    5.3    5.0    4.8    4.5
Momence               2.2    2.2    2.1    1.9    1.8    1.7    1.6
:Iroquois River
Rensselaer            4.9    4.8    4.7    4.4    4.2    4.0    4.0
Foresman              7.6    7.4    7.0    6.6    6.1    5.8    5.7
Iroquois              8.8    8.6    8.0    7.4    6.7    6.2    6.1
:Sugar Creek
Milford               4.1    3.9    3.8    3.7    3.5    3.4    3.4
:Iroquois River
Chebanse              4.5    4.3    4.1    3.8    3.6    3.3    3.2
:Kankakee River
Wilmington            2.0    2.0    1.9    1.8    1.7    1.5    1.5
:Mazon River
Coal City             1.9    1.9    1.8    1.7    1.6    1.4    1.3
:Vermilion River
Pontiac               3.6    3.6    3.5    3.4    3.2    3.1    3.0
Leonore               4.7    4.5    4.4    4.2    4.1    3.9    3.7
:Hart Ditch
Dyer                  2.1    2.0    2.0    2.0    1.9    1.9    1.8
:Thorn Creek
Thornton              3.0    3.0    3.0    2.9    2.9    2.8    2.8
:Little Calumet River
Munster (Hohman A     5.8    5.7    5.6    5.5    5.4    5.3    5.3
South Holland         5.8    5.8    5.6    5.5    5.5    5.4    5.3
:Illinois River
Morris                5.3    5.3    5.1    5.0    4.9    4.9    4.8
Ottawa              458.7  458.7  458.6  458.6  458.5  458.5  458.5
La Salle             12.1   12.1   11.8   11.6   11.2   11.0   10.9

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/lot for more weather and water
information.

The next outlook will be issued

$$






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