Flood Potential Outlook
Issued by NWS Milwaukee/Sullivan, WI

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PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1118 AM CST THU FEB 15 2024

...Spring Flood Outlook...

The risk of spring flooding is average to below average across
southern Wisconsin. Basins with below average risk include: The
lower Wisconsin, Baraboo, Pecatonica, Sugar, Upper Fox, and
Sheboygan. Basins with near to below average risk include: The
Crawfish, Rock, and Turtle Creek. Basins with near average risk
include: Lower Fox, Root, Cedar Creek, and Milwaukee. Flooding is
still possible, but the underlying risk is not elevated at this
time. The greatest potential for flooding will be tied to heavy rain.


...Flood Outlook Factors...

Despite the lack of a snowpack, precipitation for the winter months
has been average to above average. Precipitation since December 1 is
75-125 percent of normal across most of southern Wisconsin and 125-
150 percent of normal in far southeast Wisconsin. Since January 1
these values are 100-150 percent of normal.

Due to the mild temperatures, most of the precipitation has been in
the form of rain and not snow. Almost all of the snow from early to
mid Janurary has melted. As a result, streamflows are above normal.
Streamflow values averaged over the past 14 days are in the 60-90th
percentile. The lack of a snowpack, offset by the average to above
average precipitation and above average streamflow, results in the
average to below average flood risk. In southeast Wisconsin,
streamflows exceed the 90th percentile in some locations,
contributing to the near average flood risk.

Soil moisture is near average across south-central and southeast
Wisconsin and below average across southern Wisconsin. The summmer
drought is still having some influce on soil moisture, especially in
southwest and south-central Wisconsin. Most frost depth sensors in
southern Wisconsin are reporting no frost. This means there is
greater potential for precipitation and melting snow to soak into
the ground, lowering the flood risk.

River are mainly ice free, so the ice jam risk is low. However some
lakes are still ice covered so ice may make its way downstream and
could cause some jam issues.

Little precipitation is expected over the next week. The outlook for
late February indicates enhanced odds of above average temperature
and equal chances of above, near and below average precipitation.
The outlook for March-April-May indicates enhances odds of above
average temperature and equal chances of above, near and below
average precipitation.


...Probabilistic Forecast Information for River Forecast Points...

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
--------           -----  -----  ----- : ---  ---  ---  ---  ---  ---
:Rock River
Watertown            5.5    6.0    6.5 :   7   14   <5   10   <5    5
:Crawfish River
Milford              7.0    9.0   10.0 :  20   35   <5    8   <5    6
:Rock River
Jefferson           10.0   11.0   13.0 :  23   36   14   25   <5    6
Fort Atkinson       16.0   17.0   18.0 :  10   17   <5    7   <5   <5
Lake Koshkonong     10.0   11.0   11.5 :  32   42   18   30   14   23
Afton                9.0   11.1   12.2 :  32   41   10   16   <5    8
:Turtle Creek
Clinton              8.0   10.0   12.0 :   9   14   <5    6   <5   <5
Beloit               7.5   10.5   12.5 :   8   14   <5   <5   <5   <5
:Pecatonica River
Darlington          13.5   15.0   16.0 :  <5    5   <5   <5   <5   <5
:East Branch Pecatonica River
Blanchardville      11.0   14.0   16.0 :   7   14   <5   <5   <5   <5
:Pecatonica River
Martintown          13.5   18.0   21.0 :  13   23   <5   <5   <5   <5
:Sugar River
Albany              12.0   13.0   14.0 :  <5   <5   <5   <5   <5   <5
Brodhead             5.0    8.0   10.0 :  23   41   <5   10   <5   <5
:Wisconsin River
Wisconsin Dells     16.0   17.6   18.9 :   9   26   <5   14   <5    7
Portage             17.0   18.0   19.0 :  34   71   21   52    6   26
:Baraboo River
Reedsburg           14.0   16.0   18.0 :  39   43   19   30    5   11
Rock Springs        18.5   21.0   23.0 :  20   33   12   26   <5    6
West Baraboo         9.0   10.5   12.5 :  <5   11   <5   <5   <5   <5
Baraboo             16.0   22.0   23.1 :  23   38   <5   <5   <5   <5
:Black Earth Creek
Black Earth          5.5    7.0    8.0 :  <5   <5   <5   <5   <5   <5
:Fox River
Princeton            9.5   11.0   12.0 :   7   19   <5   <5   <5   <5
Berlin              13.0   14.5   16.0 :  15   25   <5   <5   <5   <5
:Sheboygan River
Sheboygan            8.0   10.0   12.0 :  17   30    6    7   <5   <5
:Root River
Franklin             8.0   10.0   12.0 :  21   25   <5   <5   <5   <5
:Root River Canal
Raymond              9.0   11.0   12.0 :  21   24   <5   <5   <5   <5
:Root River
Racine               7.0    7.5    8.0 :  <5    8   <5   <5   <5   <5
:Cedar Creek
Cedarburg           10.0   11.0   12.0 :  <5   <5   <5   <5   <5   <5
:Milwaukee River
Cedarburg           11.0   13.0   14.0 :  27   38    5    8   <5   <5
:Fox River Lower
Waukesha             6.0    8.0   10.0 :   8   12   <5    6   <5   <5
Burlington          11.0   12.0   14.0 :  15   22    5   14   <5   <5
New Munster         11.0   13.0   14.0 :  71   69   24   30    6   18

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%
--------            ------ ------ ------ ------ ------ ------ ------
:Rock River
Watertown             3.2    3.2    3.4    4.0    4.6    5.2    5.9
:Crawfish River
Milford               3.3    3.5    4.3    5.5    6.5    8.0    8.5
:Rock River
Jefferson             6.1    6.1    6.8    7.9    9.8   11.3   12.2
Fort Atkinson        12.6   12.7   13.1   13.8   14.9   16.0   16.7
Lake Koshkonong       7.4    7.5    8.1    9.2   10.4   11.9   12.6
Afton                 6.2    6.2    7.0    8.2    9.5   11.2   12.1
:Turtle Creek
Clinton               4.7    4.8    5.1    5.7    6.4    7.8    9.1
Beloit                4.4    4.5    4.8    5.3    6.0    7.1    8.5
:Pecatonica River
Darlington            4.2    4.4    4.9    5.5    7.6    9.7   11.5
:East Branch Pecatonica River
Blanchardville        5.8    6.1    6.8    8.3    9.9   10.9   12.0
:Pecatonica River
Martintown            7.1    7.3    8.1   10.1   12.2   13.9   14.7
:Sugar River
Albany                4.8    5.1    5.8    7.0    8.3    9.7   10.5
Brodhead              1.8    2.0    2.5    3.7    4.8    5.8    7.1
:Wisconsin River
Wisconsin Dells       5.5    6.5    8.3   10.6   12.7   15.5   16.6
Portage              11.8   12.4   13.4   16.0   17.4   18.4   19.0
:Baraboo River
Reedsburg             8.3    9.2   11.1   13.2   15.0   17.0   18.1
Rock Springs         11.0   11.6   13.3   15.7   18.0   21.5   22.2
West Baraboo          3.2    3.6    4.5    5.3    6.1    7.7    8.3
Baraboo               9.6   10.3   12.4   14.3   15.8   18.1   18.9
:Black Earth Creek
Black Earth           2.8    2.8    3.0    3.4    3.9    4.3    4.5
:Fox River
Princeton             5.7    6.3    6.9    7.6    8.3    9.3   10.1
Berlin               10.3   10.7   11.2   11.8   12.4   13.2   14.0
:Sheboygan River
Sheboygan             3.7    4.4    5.1    6.2    7.5    8.6   10.5
:Root River
Franklin              4.6    5.7    6.4    6.9    7.4    8.4    8.8
:Root River Canal
Raymond               4.2    4.8    6.5    7.5    8.8   10.1   10.5
:Root River
Racine                3.8    4.2    4.6    5.0    5.5    6.2    6.8
:Cedar Creek
Cedarburg             6.7    6.9    7.4    8.1    8.8    9.3    9.8
:Milwaukee River
Cedarburg             7.7    8.0    8.8    9.8   11.1   12.1   13.2
:Fox River Lower
Waukesha              3.9    4.1    4.5    4.9    5.4    5.7    7.8
Burlington            7.9    8.3    9.0    9.9   10.8   11.4   12.1
New Munster           9.2    9.8   10.9   12.0   13.0   13.8   14.5

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: 02/19/2024 - 05/19/2024
Location              95%    90%    75%    50%    25%    10%     5%
--------            ------ ------ ------ ------ ------ ------ ------
:Rock River
Watertown             2.4    2.4    2.2    2.1    1.9    1.6    1.6
:Crawfish River
Milford               2.6    2.5    2.4    2.3    2.1    2.0    2.0
:Rock River
Jefferson             4.4    4.1    3.8    3.5    3.1    2.9    2.9
Fort Atkinson        11.8   11.7   11.5   11.3   11.1   10.9   10.9
Lake Koshkonong       6.9    6.7    6.2    5.8    5.8    5.8    5.7
Afton                 5.9    5.7    5.6    4.4    3.7    2.7    2.6
:Turtle Creek
Clinton               4.0    3.9    3.8    3.7    3.7    3.6    3.6
Beloit                4.0    3.9    3.8    3.6    3.5    3.5    3.5
:Pecatonica River
Darlington            3.2    3.2    3.1    3.0    2.8    2.7    2.6
:East Branch Pecatonica River
Blanchardville        5.0    4.9    4.7    4.6    4.3    4.2    4.1
:Pecatonica River
Martintown            6.7    6.5    6.2    6.0    5.6    5.5    5.4
:Sugar River
Albany                4.3    4.2    4.0    3.9    3.8    3.8    3.7
Brodhead              1.4    1.3    1.2    1.1    0.9    0.9    0.9
:Wisconsin River
Wisconsin Dells       2.5    2.1    1.9    1.9    1.5    1.1    0.9
Portage               9.6    9.4    9.2    9.1    8.8    8.5    8.3
:Baraboo River
Reedsburg             4.1    3.9    3.5    3.3    3.1    3.0    2.9
Rock Springs          8.0    7.9    7.7    7.6    7.5    7.5    7.4
West Baraboo          2.6    2.5    2.5    2.5    2.5    2.5    2.5
Baraboo               6.8    6.7    6.4    6.2    6.1    6.0    6.0
:Black Earth Creek
Black Earth           2.2    2.2    2.2    2.2    2.1    2.1    2.1
:Fox River
Princeton             4.7    4.6    4.5    4.4    4.2    4.0    3.9
Berlin                9.5    9.4    9.3    9.2    9.1    8.9    8.8
:Sheboygan River
Sheboygan             2.3    2.3    2.2    2.1    2.0    2.0    1.9
:Root River
Franklin              2.3    2.3    2.2    2.2    2.1    2.0    2.0
:Root River Canal
Raymond               2.5    2.4    2.4    2.3    2.2    2.2    2.1
:Root River
Racine                2.8    2.7    2.6    2.5    2.4    2.4    2.3
:Cedar Creek
Cedarburg             5.6    5.6    5.5    5.4    5.3    5.2    5.2
:Milwaukee River
Cedarburg             6.1    6.0    5.9    5.7    5.6    5.6    5.5
:Fox River Lower
Waukesha              3.1    3.0    2.9    2.9    2.8    2.8    2.7
Burlington            7.2    7.1    6.9    6.7    6.5    6.4    6.3
New Munster           7.7    7.5    7.2    6.8    6.5    6.3    6.3

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 National Weather Service`s advanced hydrologic prediction
service.

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

The next outlook will be issued Feb 29, 2024.

Marquardt

$$


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