Flood Potential Outlook
Issued by NWS La Crosse, WI
Issued by NWS La Crosse, WI
935
FGUS73 KARX 131511
ESFARX
IAC005-037-043-065-067-089-131-191-MNC039-045-055-099-109-157-169-
WIC001-011-019-023-043-053-057-063-081-103-119-121-123-282359-
Probabilistic Hydrologic Outlook
National Weather Service La Crosse WI
833 AM CST Thu Feb 13 2025
...FIRST OF THREE PLANNED 2025 SPRING FLOOD AND WATER RESOURCES
OUTLOOK...
The overall risk for flooding this spring is below-normal along the
mainstem of the Mississippi River and its associated tributaries
across southeast Minnesota, northeast Iowa, and southwest Wisconsin.
This information is the first of three planned spring flood and
water resources outlooks providing spring snowmelt and flood
potential information for this upcoming spring. The information that
goes into this outlook was collected from a number of National
Weather Service partners including: United States Geological Survey,
US Army Corps of Engineers, Midwestern Regional Climate Center, US
Drought Monitor, Climate Prediction Center, NASA, MN DNR, and NOAAs
Office of Water Prediction.
This outlook is a summary of the past and present basin conditions
for parts of southeast Minnesota, northeast Iowa, and southwest into
central Wisconsin.
To view the NWS La Crosse 2025 Spring Hydrologic Outlook storymap,
which includes a more detailed description of the flood outlook and
images, refer to: https://www.weather.gov/ARX and select the 2025
Spring Hydrologic Outlook news headline near the top of the page.
...FLOOD POTENTIAL SUMMARY HIGHLIGHTS...
The overall flood risk for the Upper Mississippi River Basin is
BELOW NORMAL.
...Past Precipitation...
From September 1 through November 30 (meteorological autumn),
precipitation totals ranged from 3.58 near Oelwein, IA to 11.16 near
Hillsboro, WI. Precipitation anomalies ranged from 4 inches drier
than normal to 1 inch wetter than normal. During this same time
period, temperature anomalies ranged from 3 to 5F warmer than
normal. This dryness and above-normal temperatures resulted in
abnormally dry (D0) to moderate (D1) drought conditions. There was
even a brief period of severe (D2) drought mainly along and west of
the Mississippi River in mid- and late October (maxing out at 40% of
the NWS La Crosse Hydrologic Service Area on October 29).
This dryness continued into meteorological winter. From December 1
through February 10, precipitation totals ranged from 1.13 near
Cashton, WI to 2.78 near Medford, WI. This resulted in precipitation
anomalies ranging from near-normal to 2.5 inches drier than normal
for the winter.
Overall since September 1, 2024, precipitation anomalies range from
near-normal to 6 inches below-normal. The largest deficits are
mainly along and west of the Mississippi River and near-normal
conditions are mainly found in central Wisconsin.
...River Conditions...
Overall, the amount of water currently moving through our rivers is
below the long-term normal for this time of year. Lack of snowmelt
runoff this year, due to a below-normal seasonal snowfall, is the
main contributor.
...Soil Moisture and Frost Depths...
Last September, most of the region was in an "abnormally dry" to
"moderate drought" status per the U.S. Drought Monitor. Since then,
drought has expanded slightly across the region. Due to the drought,
soil moisture across the region is below normal.
Due to the periodic shots of arctic air this winter, frost depths
are well above normal for this time of year. Our entire region has
12 to upwards of 30 inches of frost and any future precipitation
will be very slow to absorb into the soils until the frost
dissipates. Much of the flood threat this spring hinges on any
heavier spring rains falling on frozen soil, running off into the
rivers more quickly.
...Snow Cover and Liquid Water Content...
A lack of precipitation this winter has left little to no snowpack
for a spring melt runoff. While there is still time for additional
snowfall and precipitation to fall, our current snow pack is
expected to play little to no role in increasing streamflows at this
time.
...River Ice Conditions...
Periods of well-below normal temperatures has allowed for ice to
develop on area rivers. This ice could lead to elevated river levels
if a rapid warm up and precipitation occurs concurrently.
...Weather Outlook...
The above conditions can and often change. The biggest factor
affecting spring flood risks is the weather conditions during the
sensitive period of melting snow. This year, without the presence of
a snowpack, future precipitation is the main driver of any flood
risk moving forward.
From February 20-26 (8-14 days), the Climate Prediction Center is
forecasting enhanced chances for colder- (40-50%) and drier- (33-
50%) than normal conditions. Typically, normal (1991-2020)
temperatures range from 21 to 26F and precipitation ranges from
0.25 to 0.30 inches.
Looking ahead to March, the CFS version 2 model has been trending
toward warmer-than-normal temperatures over the past week. This
would be supported by Madden Julian Oscillation moving east through
the Indian Ocean (Phases 2 and 3) in early and mid-March. As far as
precipitation, the CFS version 2 continues to favor enhanced chances
for wetter-than-normal conditions. This would favor the wetter
trends over the past 15 Marches for Rochester (8 have been among the
wettest third, 3 near normal, and 4 among the driest third).
Meanwhile, La Crosse has trended toward near-normal (7 out of 15
were near normal and the other 8 were equally split between the
wettest and driest third) during these same Marches. Besides trends,
there is also a weak La Nia in the eastern and central tropical
Pacific. These typically cause enhanced chances for wetter-than-
normal conditions during February and March from the Mid-Mississippi
River Valley into the eastern Great Lakes. This wet pattern will
occasionally shift northwest into our region. However, with this
being a weak La Nia, it is less likely to result in conventional
winter/spring impacts.
...Definitions...
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 greater 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.
The term minor flooding is used to indicate minimal or no property
damage. However, some public inconvenience is possible.
The term moderate flooding is used to indicate some inundations of
structures and roads near streams. Some evacuations of people and/or
transfer of property to higher elevations may be needed.
The term major flooding is used to indicate extensive inundations of
structures and roads. Significant evacuations of people and/or
transfer of property to higher elevations will be needed.
...Table 1--Probabilities for Minor, Moderate and Major Flooding...
Valid Period: 02/17/2025 - 05/18/2025
: 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
-------- ----- ----- ----- : --- --- --- --- --- ---
:Mississippi River
Lake City 16.0 18.0 20.0 : 15 28 8 9 <5 6
Wabasha 12.0 14.0 16.0 : 26 57 11 23 <5 8
Alma Dam 4 16.0 17.0 18.0 : <5 7 <5 6 <5 <5
MN City Dam 5 660.0 662.0 665.0 : 15 31 10 16 <5 6
Winona Dam 5A 655.0 659.0 661.0 : 18 40 7 9 <5 6
Winona 13.0 15.0 18.0 : 20 46 13 25 <5 9
Trempealeau 647.0 649.0 651.0 : 18 38 10 19 <5 6
La Crescent 641.0 643.0 645.0 : 15 34 10 15 <5 7
La Crosse 12.0 13.0 15.5 : 20 47 14 28 <5 8
Genoa 631.0 634.0 636.0 : 21 51 10 14 <5 7
Lansing 17.0 19.0 20.0 : 10 11 <5 7 <5 <5
Lynxville 625.0 628.0 631.0 : 13 26 7 9 <5 <5
McGregor 16.0 19.0 22.0 : 28 55 13 32 7 10
Guttenberg 15.0 18.0 21.0 : 26 49 11 17 <5 5
:Zumbro River
Zumbro Falls 18.0 24.0 26.0 : 17 10 <5 <5 <5 <5
:South Fork Zumbro River
Rochester 14.0 18.0 20.0 : 16 <5 <5 <5 <5 <5
:Root River
Houston 15.0 17.0 18.0 : 21 7 <5 <5 <5 <5
:South Branch Root River
Lanesboro 12.0 16.0 18.0 : <5 <5 <5 <5 <5 <5
:Cedar River
Lansing 18.0 20.0 22.0 : <5 6 <5 <5 <5 <5
Austin 15.0 18.0 20.0 : <5 7 <5 5 <5 <5
Charles City 12.0 15.0 18.0 : 7 20 <5 7 <5 6
:Turtle Creek
Austin 10.5 12.0 14.0 : 6 14 <5 9 <5 <5
:Turkey River
Spillville 9.0 11.0 13.0 : 59 44 43 31 23 15
Elkader 12.0 16.0 20.0 : 51 45 20 16 <5 <5
Garber 17.0 20.0 23.0 : 44 34 22 20 9 7
:Upper Iowa River
Bluffton 14.0 16.0 18.0 : <5 <5 <5 <5 <5 <5
Decorah 12.0 13.0 14.0 : <5 <5 <5 <5 <5 <5
Dorchester 14.0 17.0 19.0 : 31 20 12 7 <5 <5
:Trempealeau River
Arcadia 8.0 9.0 10.0 : 14 23 <5 <5 <5 <5
Dodge 10.5 11.0 12.0 : 9 12 7 5 <5 <5
:Black River
Neillsville 18.0 20.0 22.0 : <5 <5 <5 <5 <5 <5
Black River Falls 47.0 51.0 55.0 : 44 57 17 27 <5 9
Galesville 12.0 13.0 15.0 : 41 54 22 37 <5 <5
:Kickapoo River
La Farge 12.0 13.0 14.0 : <5 <5 <5 <5 <5 <5
Viola 14.0 16.0 18.0 : 11 7 <5 <5 <5 <5
Readstown 11.0 14.0 16.0 : 28 27 <5 <5 <5 <5
Soldiers Grove 13.0 16.0 19.0 : 17 16 <5 <5 <5 <5
Gays Mills 13.0 15.0 17.0 : 46 39 <5 <5 <5 <5
Steuben 12.0 13.0 15.0 : 11 14 <5 <5 <5 <5
:Wisconsin River
Muscoda 9.0 10.0 11.0 : 13 19 <5 7 <5 <5
:Yellow River
Necedah 15.0 16.5 18.0 : 50 74 21 47 6 17
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: 02/17/2025 - 05/18/2025
Location 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Mississippi River
Lake City 8.2 9.4 10.8 12.2 14.0 17.2 18.4
Wabasha 8.2 9.0 9.8 11.0 12.1 14.6 15.7
Alma Dam 4 5.9 6.8 7.8 9.1 10.8 14.2 15.4
MN City Dam 5 652.3 653.2 654.4 655.9 657.9 662.4 663.4
Winona Dam 5A 647.1 648.3 649.9 651.4 653.5 658.2 659.3
Winona 6.3 6.9 8.0 9.9 11.9 16.8 17.9
Trempealeau 641.0 641.8 642.9 644.1 645.6 649.4 650.1
La Crescent 634.2 634.8 636.2 637.9 639.3 643.3 644.1
La Crosse 6.4 6.8 8.1 9.7 11.1 14.6 15.3
Genoa 625.0 625.5 627.2 629.1 630.4 634.3 635.0
Lansing 8.6 8.7 9.5 10.8 12.1 16.9 17.8
Lynxville 617.1 617.6 619.1 620.6 622.4 627.3 628.2
McGregor 9.8 10.9 11.9 13.8 16.9 21.1 22.2
Guttenberg 8.9 9.9 11.1 12.7 15.1 18.2 19.4
:Zumbro River
Zumbro Falls 6.4 7.5 9.5 11.7 14.4 20.3 21.3
:South Fork Zumbro River
Rochester 3.3 3.6 4.8 6.9 11.6 15.0 16.6
:Root River
Houston 5.4 6.7 8.3 11.8 14.7 16.1 16.8
:South Branch Root River
Lanesboro 3.9 4.8 5.8 7.2 8.7 10.1 10.9
:Cedar River
Lansing 11.5 12.1 13.1 13.8 15.1 15.8 16.5
Austin 5.7 6.1 6.9 8.3 10.1 11.0 12.4
Charles City 3.7 3.9 4.9 6.7 8.5 10.5 13.0
:Turtle Creek
Austin 3.4 3.8 4.9 6.2 7.7 9.5 11.1
:Turkey River
Spillville 3.2 3.7 6.9 10.5 12.9 14.6 16.6
Elkader 7.8 8.4 9.8 12.2 15.7 17.9 19.1
Garber 8.5 9.0 11.4 15.0 19.4 22.5 24.7
:Upper Iowa River
Bluffton 4.5 4.9 5.5 6.1 7.0 7.9 8.8
Decorah 2.9 3.1 3.5 4.8 6.5 8.0 9.1
Dorchester 8.2 8.6 9.2 11.5 15.4 18.0 19.0
:Trempealeau River
Arcadia 4.4 4.8 5.7 7.3 7.8 8.3 8.6
Dodge 6.8 7.3 8.3 8.8 9.5 10.3 11.1
:Black River
Neillsville 7.5 8.2 8.8 10.4 12.5 13.8 14.8
Black River Falls 40.9 42.0 43.2 46.0 49.9 52.7 54.0
Galesville 7.6 8.5 9.7 11.3 12.8 13.5 13.9
:Kickapoo River
La Farge 5.2 5.4 6.2 7.1 8.8 10.2 10.8
Viola 9.5 9.7 10.2 10.9 12.5 14.1 14.4
Readstown 6.5 6.9 8.2 10.0 11.1 12.0 12.2
Soldiers Grove 7.5 8.2 9.5 11.8 12.7 13.4 13.7
Gays Mills 8.7 9.0 10.5 12.5 13.4 14.1 14.2
Steuben 8.2 8.5 9.4 10.2 11.3 12.1 12.2
:Wisconsin River
Muscoda 4.2 4.5 4.9 6.8 8.1 9.3 9.7
:Yellow River
Necedah 12.3 13.0 13.9 14.9 16.4 17.7 18.5
In Table 3 below, the 95 through 5 percent columns indicate the
probability of falling below the listed flows (kcfs) for
the valid time period.
...Table 3--Nonexceedance Probabilities...
Chance of Falling Below Flows (kcfs)
At Specific Locations
Valid Period: 02/17/2025 - 05/18/2025
Location 95% 90% 75% 50% 25% 10% 5%
-------- ------ ------ ------ ------ ------ ------ ------
:Mississippi River
Lake City 13.9 13.4 12.7 11.7 11.1 10.8 10.4
Wabasha 13.9 13.4 12.7 11.7 11.1 10.8 10.4
Alma Dam 4 14.4 13.8 13.1 12.1 11.4 11.1 10.7
MN City Dam 5 15.2 14.5 13.6 12.6 11.9 11.6 11.3
Winona Dam 5A 15.7 15.0 13.8 12.9 12.1 11.9 11.5
Winona 15.7 15.1 13.8 12.9 12.1 11.9 11.5
Trempealeau 16.6 16.1 14.8 13.6 12.6 12.3 12.0
La Crescent 18.0 17.6 16.0 14.5 13.4 13.0 12.9
La Crosse 18.2 18.0 16.4 14.8 13.7 13.4 13.3
Genoa 19.0 19.0 17.4 15.6 14.5 14.2 14.0
Lansing 19.2 19.1 18.0 16.3 15.0 14.8 14.5
Lynxville 19.3 19.3 18.4 16.6 15.2 15.0 14.7
McGregor 18.9 18.8 18.8 17.2 15.4 15.2 14.9
Guttenberg 22.8 22.8 22.8 22.7 21.4 21.1 20.3
:Zumbro River
Zumbro Falls 0.2 0.2 0.2 0.2 0.2 0.2 0.2
:South Fork Zumbro River
Rochester 0.1 0.1 0.1 0.1 0.1 0.1 0.1
:Root River
Houston 0.4 0.4 0.4 0.4 0.4 0.4 0.4
:South Branch Root River
Lanesboro 0.1 0.1 0.1 0.1 0.1 0.1 0.1
:Cedar River
Lansing 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Austin 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Charles City 0.2 0.2 0.2 0.2 0.2 0.2 0.2
:Turtle Creek
Austin 0.0 0.0 0.0 0.0 0.0 0.0 0.0
:Turkey River
Spillville 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Elkader 0.2 0.2 0.1 0.1 0.1 0.1 0.1
Garber 0.3 0.3 0.3 0.3 0.3 0.3 0.3
:Upper Iowa River
Bluffton 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Decorah 0.1 0.1 0.1 0.1 0.1 0.1 0.1
Dorchester 0.1 0.1 0.1 0.1 0.1 0.1 0.1
:Trempealeau River
Arcadia 0.3 0.3 0.3 0.3 0.3 0.3 0.3
Dodge 0.3 0.3 0.3 0.3 0.3 0.3 0.3
:Black River
Neillsville 0.1 0.1 0.1 0.1 0.1 0.1 0.1
Black River Falls 0.3 0.3 0.3 0.3 0.3 0.3 0.3
Galesville 0.6 0.6 0.6 0.6 0.5 0.5 0.5
:Kickapoo River
La Farge 0.1 0.1 0.1 0.1 0.1 0.1 0.1
Viola 0.2 0.2 0.2 0.2 0.2 0.2 0.2
Readstown 0.3 0.3 0.3 0.3 0.3 0.2 0.2
Soldiers Grove 0.3 0.3 0.3 0.3 0.3 0.3 0.3
Gays Mills 0.3 0.3 0.3 0.3 0.3 0.3 0.3
Steuben 0.4 0.4 0.4 0.4 0.4 0.4 0.4
:Wisconsin River
Muscoda 2.2 2.2 2.2 2.2 2.2 2.2 2.2
:Yellow River
Necedah 0.1 0.1 0.1 0.1 0.1 0.1 0.1
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 and 90 day long-range
outlooks of temperature and precipitation. By providing a range
of probabilities...the level of rise associated with long-range
planning decisions can be determined. These probabilistic forecasts
are part of the National Weather Service`s National Water Prediction
Service.
All of this information is also available in graphical format
on the internet at:
https://www.weather.gov/lacrosse
The next outlook will be issued on February 27th, 2025.
$$
JAW/Boyne