Flood Potential Outlook
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
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FGUS73 KMKX 271815
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WIC077-047-039-117-111-021-027-131-089-049-025-055-133-079-065-045-
105-127-101-059-282100-
PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1214 PM CST THU FEB 27 2025
...Spring flood outlook for southern Wisconsin...
The risk of flooding this spring is below average for most of
southern Wisconsin. The exception is the Baraboo River where the
risk is average to below average. The basins included in the below
are risk are:the lower Wisconsin, Black Earth Creek, Pecatonica,
Sugar, Sheboygan, Upper Fox, Rock, Lower Fox, Root, Cedar Creek, and
Milwaukee river basins.
Factors that play into this risk are a below average snow pack,
average to below average soil moisture, average to below average
streamflow, offset by average to above average frost depth. The
spring flood risk pertains to the 3 month time period from March 3
to June 1, while the risk for individual weather events could be
greater. The spring flood risk could change with additional snow.
Precipitation since October 1 is 75-125% of normal northeast and
southwest of Madison and 25-75% of normal in southeast Wisconsin.
Since December 1, precipitation is 25-50% of normal across much of
southern Wisconsin, which is 1.5 to 3.5 inches below normal. The
U.S. Drought Monitor indicates Moderate drought conditions in
southeast Wisconsin. Soil moisture from the CPC Calculated Soil
Moisture product is in the 10-30th percentile in southeast Wisconsin
and in the 30-70th percentile across the remainder of southern
Wisconsin. This means there is some room in the soil to absorb
additional moisture. Streamflows in southeast Wisconsin are in the
10-24th percentile and in the 25-75th percentile across the rest of
southern Wisconsin. This means there is some room in the rivers to
contain additional rainfall and snowmelt.
Snowfall this winter is 10 to 20 inches below average. There is
little to no snow across southern Wisconsin, which plays a large
role in the spring flood risk. There is 1 to 2 inches of snow water
equivalent in the headwaters of the Wisconsin River, which is one
quarter to one half of normal. Frost depth is 1 to 3 feet, which is
deeper than average. This means less infiltration into the soils
while the ground is still frozen.
...Weather Outlook...
Over the next week, mild temperatures are expected which will help
thaw the ground and melt any remaining snow piles. There is a chance
for rain. Two weeks from now, March 6-12, there are enhanced odds
for above average temperature and near average precipitation. The
outlook for the March, April, May season shows equal chances for
above, near and below average temperature and enhanced odds for
above average precipitation.
Visit our web site weather.gov/mkx/SpringFloodOutlook for spring
flood outlook information.
The next outlook will be issued March 13, 2025.
...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: 03/03/2025 - 06/01/2025
: 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
-------- ----- ----- ----- : --- --- --- --- --- ---
:Rock River
Watertown 5.5 6.0 6.5 : <5 16 <5 11 <5 5
:Crawfish River
Milford 7.0 9.0 10.0 : 16 39 <5 10 <5 7
:Rock River
Jefferson 10.0 11.0 13.0 : 13 37 8 26 <5 7
Fort Atkinson 16.0 17.0 18.0 : 6 19 <5 9 <5 <5
Lake Koshkonong 10.0 11.0 11.5 : 18 43 11 31 8 24
Afton 9.0 11.1 12.2 : 18 43 7 17 <5 10
:Turtle Creek
Clinton 8.0 10.0 12.0 : 7 13 <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 : 9 15 <5 <5 <5 <5
:Pecatonica River
Martintown 13.5 18.0 21.0 : 9 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 : 24 36 <5 8 <5 <5
:Wisconsin River
Wisconsin Dells 16.0 17.6 18.9 : 8 25 <5 13 <5 7
Portage 17.0 18.0 19.0 : 40 71 23 52 6 24
:Baraboo River
Reedsburg 14.0 16.0 18.0 : 31 37 14 22 7 12
Rock Springs 18.5 21.0 23.0 : 28 37 12 21 6 13
West Baraboo 9.0 10.5 12.5 : 7 14 <5 6 <5 <5
Baraboo 16.0 22.0 23.1 : 32 42 <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 20 <5 <5 <5 <5
Berlin 13.0 14.5 16.0 : 11 24 <5 <5 <5 <5
:Sheboygan River
Sheboygan 8.0 10.0 12.0 : 11 28 6 8 <5 6
:Root River
Franklin 8.0 10.0 12.0 : 20 26 <5 <5 <5 <5
:Root River Canal
Raymond 9.0 11.0 12.0 : 15 22 <5 5 <5 <5
:Root River
Racine 7.0 7.5 8.0 : <5 9 <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 : 14 38 <5 9 <5 5
:Fox River Lower
Waukesha 6.0 8.0 10.0 : 8 16 <5 7 <5 <5
New Munster 11.0 13.0 14.0 : 22 51 7 22 <5 16
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: 03/03/2025 - 06/01/2025
Location 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Rock River
Watertown 2.1 2.4 2.8 3.6 4.2 4.7 5.4
:Crawfish River
Milford 2.7 3.1 3.6 4.8 6.2 7.9 8.9
:Rock River
Jefferson 4.2 5.2 5.7 7.1 8.9 10.6 11.9
Fort Atkinson 11.3 11.9 12.3 13.2 14.2 15.7 16.1
Lake Koshkonong 6.2 6.2 6.7 8.3 9.5 11.2 12.0
Afton 4.9 5.3 5.8 7.4 8.5 10.6 11.4
:Turtle Creek
Clinton 3.9 4.1 4.4 5.0 5.5 6.9 8.3
:Pecatonica River
Darlington 4.1 4.3 4.7 5.5 7.5 10.5 11.9
:East Branch Pecatonica River
Blanchardville 6.0 6.3 6.6 7.8 9.8 10.8 12.1
:Pecatonica River
Martintown 6.9 7.1 7.7 8.8 11.2 13.2 14.3
:Sugar River
Albany 4.8 5.0 5.6 6.5 8.4 10.2 10.9
Brodhead 1.8 2.0 2.3 3.2 4.9 6.5 7.5
:Wisconsin River
Wisconsin Dells 7.2 7.8 8.9 10.9 13.3 14.5 16.7
Portage 12.9 13.2 13.9 16.4 18.0 18.3 19.2
:Baraboo River
Reedsburg 6.8 7.3 9.6 11.9 14.5 16.6 18.5
Rock Springs 11.0 11.8 13.6 15.6 18.8 21.8 23.4
West Baraboo 3.3 3.7 4.6 5.5 6.4 8.2 10.0
Baraboo 9.3 10.1 12.2 14.5 16.5 19.1 20.9
:Black Earth Creek
Black Earth 2.6 2.6 2.7 3.1 3.6 4.1 4.3
:Fox River
Princeton 6.0 6.2 6.7 7.4 8.2 9.2 10.1
Berlin 10.1 10.2 10.7 11.3 12.0 13.1 13.9
:Sheboygan River
Sheboygan 3.1 3.4 4.2 5.3 6.7 8.1 11.2
:Root River
Franklin 2.8 3.9 5.5 6.5 7.4 8.3 8.6
:Root River Canal
Raymond 4.3 4.7 6.0 7.3 8.3 9.7 10.3
:Root River
Racine 3.4 3.7 4.3 4.7 5.3 6.1 6.7
:Cedar Creek
Cedarburg 6.0 6.1 6.8 7.5 8.3 9.0 9.4
:Milwaukee River
Cedarburg 6.9 7.1 7.8 9.0 10.0 11.5 12.0
:Fox River Lower
Waukesha 3.4 3.5 3.9 4.5 5.1 5.5 6.2
New Munster 6.2 7.1 8.0 9.9 10.7 12.1 13.9
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: 03/03/2025 - 06/01/2025
Location 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Rock River
Watertown 0.3 0.3 0.3 0.3 0.2 0.2 0.1
:Crawfish River
Milford 0.4 0.3 0.2 0.2 0.1 0.1 0.1
:Rock River
Jefferson 0.7 0.7 0.7 0.5 0.4 0.3 0.3
Fort Atkinson 0.8 0.8 0.8 0.7 0.5 0.4 0.4
Afton 1.3 1.3 1.3 1.1 0.8 0.5 0.5
:Turtle Creek
Clinton 0.1 0.1 0.1 0.1 0.1 0.1 0.1
:Pecatonica River
Darlington 0.2 0.2 0.2 0.2 0.2 0.1 0.1
:East Branch Pecatonica River
Blanchardville 0.2 0.2 0.2 0.1 0.1 0.1 0.1
:Pecatonica River
Martintown 0.8 0.8 0.7 0.6 0.5 0.5 0.5
:Sugar River
Albany 0.3 0.3 0.3 0.3 0.2 0.2 0.2
Brodhead 0.4 0.4 0.3 0.3 0.3 0.2 0.2
:Wisconsin River
Wisconsin Dells 3.2 3.1 2.6 2.3 2.0 1.6 1.4
Portage 2.3 2.1 1.8 1.6 1.4 1.2 1.0
:Baraboo River
Reedsburg 0.1 0.1 0.1 0.1 0.1 0.1 0.1
Rock Springs 0.2 0.2 0.2 0.2 0.1 0.1 0.1
West Baraboo 0.2 0.2 0.2 0.2 0.2 0.2 0.1
Baraboo 0.3 0.3 0.2 0.2 0.2 0.2 0.2
:Black Earth Creek
Black Earth 0.0 0.0 0.0 0.0 0.0 0.0 0.0
:Fox River
Princeton 0.9 0.9 0.8 0.7 0.6 0.5 0.5
Berlin 1.2 1.2 1.2 1.0 0.9 0.8 0.7
:Sheboygan River
Sheboygan 0.2 0.1 0.1 0.1 0.1 0.1 0.1
:Root River
Franklin 0.0 0.0 0.0 0.0 0.0 0.0 0.0
:Root River Canal
Raymond 0.0 0.0 0.0 0.0 0.0 0.0 0.0
:Root River
Racine 0.1 0.1 0.0 0.0 0.0 0.0 0.0
:Cedar Creek
Cedarburg 0.0 0.0 0.0 0.0 0.0 0.0 0.0
:Milwaukee River
Cedarburg 0.3 0.2 0.2 0.1 0.1 0.1 0.1
:Fox River Lower
Waukesha 0.1 0.0 0.0 0.0 0.0 0.0 0.0
New Munster 0.4 0.4 0.3 0.3 0.2 0.2 0.2
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.
$$