Flood Potential Outlook
Issued by NWS Central Illinois

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000
FGUS73 KILX 291927
ESFILX
ILC009-017-025-033-057-079-095-101-113-123-125-129-137-143-147-
155-159-167-169-179-183-203-301930-

PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE LINCOLN IL
227 PM CDT MON SEP 29 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
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:Illinois River
Henry               23.0   24.0   31.0 :  25   12   18   12   <5   <5
Peoria              18.0   22.0   28.0 :  35   20   14    9   <5   <5
Havana              14.0   17.0   23.0 :  45   26   18   10   <5   <5
Beardstown          14.0   18.0   28.0 :  50   35   35   13   <5   <5
:Mackinaw River
Congerville 2NW     13.0   14.0   20.0 :  12    6   10    6   <5   <5
:Spoon River
London Mills        15.0   21.0   24.0 :  26   15    7   <5   <5   <5
Seville             22.0   25.0   30.0 :  25   13   12    6   <5   <5
:Sangamon River
Monticello          13.0   17.0   20.0 :  39   23    9   <5   <5   <5
Riverton            23.0   26.0   29.0 :   9   <5   <5   <5   <5   <5
Petersburg          23.0   24.0   33.0 :  12   <5    9   <5   <5   <5
:Salt Creek
Greenview           16.0   17.0   20.0 :  12   <5   12   <5   <5   <5
:Sangamon River
Oakford            471.0  472.9  478.5 :  21    9   10   <5   <5   <5
Chandlerville      456.6  459.0  462.0 :  25   13   14   <5   <5   <5
:Little Wabash River
Clay City           18.0   22.0   25.0 :  58   72    9   12   <5   <5
:Vermilion River
Danville            18.0   22.0   28.0 :  <5    7   <5   <5   <5   <5
:Embarras River
Lawrenceville       30.0   37.0   41.0 :  32   37    6    7   <5   <5
Ste. Marie          19.0   20.0   27.0 :  16   16   12   11   <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%
--------            ------ ------ ------ ------ ------ ------ ------
:Illinois River
Henry                15.3   15.7   16.2   19.7   23.5   26.8   29.8
Peoria               12.3   12.7   12.9   15.0   19.5   23.2   25.9
Havana                6.8    8.0    9.3   13.4   16.3   19.5   22.3
Beardstown           10.5   10.7   11.3   14.2   19.9   24.8   27.9
:Mackinaw River
Congerville 2NW       2.0    2.6    4.0    7.3   10.2   14.4   17.3
:Spoon River
London Mills          4.5    4.9    7.0   10.0   15.5   18.9   22.2
Seville               7.3    7.8   10.9   14.6   22.2   25.8   29.8
:Sangamon River
Monticello            8.2    9.0   11.0   12.8   13.8   16.8   17.7
Riverton              6.2    7.5   12.3   16.3   19.2   23.4   25.4
Petersburg            7.1    7.1    9.7   13.1   17.1   24.0   29.7
:Salt Creek
Greenview             3.8    4.7    7.0   10.0   14.3   17.7   18.7
:Sangamon River
Oakford             459.0  459.9  462.0  465.2  470.4  473.2  474.6
Chandlerville       446.3  447.3  449.4  452.9  457.4  459.9  461.1
:Little Wabash River
Clay City             7.8    8.7   12.6   17.9   20.4   21.9   23.0
:Vermilion River
Danville              3.0    3.5    4.7    7.7   11.3   15.1   17.4
:Embarras River
Lawrenceville        19.5   20.4   22.8   25.6   31.9   36.0   37.4
Ste. Marie            2.4    2.8    4.8    9.7   16.2   20.9   22.2

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%
--------            ------ ------ ------ ------ ------ ------ ------
:Illinois River
Henry                14.8   14.7   14.6   14.5   14.3   14.3   14.2
Peoria               11.9   11.3   10.6   10.6   10.6   10.6   10.5
Havana                5.5    5.2    5.0    4.9    4.9    4.8    4.8
Beardstown            9.9    9.8    9.6    9.2    9.1    9.1    9.1
:Mackinaw River
Congerville 2NW       1.3    1.2    1.1    1.0    0.9    0.9    0.9
:Spoon River
London Mills          3.7    3.5    3.2    2.9    2.6    2.6    2.6
Seville               6.5    6.4    6.1    5.7    5.4    5.4    5.4
:Sangamon River
Monticello            7.0    6.8    6.5    6.1    5.8    5.6    5.4
Riverton              5.1    4.8    4.1    3.6    3.3    3.0    2.9
Petersburg            6.4    6.2    5.7    5.3    5.1    5.0    4.9
:Salt Creek
Greenview             2.2    2.0    1.8    1.5    1.3    1.1    1.1
:Sangamon River
Oakford             458.0  457.7  457.2  456.7  456.4  456.3  456.2
Chandlerville       445.3  444.9  444.5  444.0  443.8  443.6  443.5

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/ilx for more weather and water
information.

These outlooks are typically issued during the third or fourth week
of the month.

$$

DRH






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