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Every spring the National Weather Service (NWS) prepares a series of flood outlooks for the potential of river flooding as a result of snow pack melt.
Each outlook takes into account anticedent conditions and current snowpack levels to anticipate the overall flood risk. The rate and timing of melt, in addition to future precipitation, can alter conditions as well.
These outlooks contain information about the potential for flooding throughout the spring months. The information can help decision makers and those with river interests prepare, in order to protect life and property.
Spring Snowmelt Flood Outlook Release Dates:
...NEAR TO SLIGHTLY BELOW NORMAL RISK OF FLOODING THIS SPRING FOR CENTRAL AND NORTHEAST WISCONSIN... This outlook references information from the following partners including: the United States Geological Survey (USGS), the U.S. Army Corps of Engineers, Regional Climate Centers, U.S. Drought Monitor, the Climate Prediction Center and NOAA`s Office of Water Prediction. This is the first of three spring flood outlooks. The next outlook will be provided on Thursday February 27th, 2025. Flood outlook factors... Soil moisture values across all of northeast Wisconsin is near normal. An area of below normal soil moisture is present in northern Wisconsin, where moderate drought (D1) persists. Overall, the lack of snowfall this winter will allow for more moisture to be absorbed into the soils and will generally decrease the flood risk. Streamflows have settled to around normal across the area after being elevated for parts of the winter thus far. This generally will result in a decrease to the overall flood risk. Snow water equivalent analysis indicated that much of northeast Wisconsin remains well-below normal, due to well-below normal snowfall. This will lead to a decreased flood risk. Frost depth this season is considered normal to above normal. This is due to the frequent cold snaps that have occurred through the winter. Frost depths currently range from 15 inches to as deep as 38 inches, which is much deeper than was observed at this time last year. The deeper frost depth may result in increased runoff as the more frozen ground will not allow water to readily pass through the surface. This is one of the primary factors that results in an increased flood risk. Lake Michigan water levels continue to run only slightly above normal which has been the case the past three years. This level will allow for decreased flooding impacts this season. For a comparison of impacts, there were very few impacts in 2022 through 2024, and Lake Michigan levels are lower this year. The frequent cold snaps for most of January and in February thus far have led to thicker ice on area rivers this season. This shows up as freezing degree days are already observed over 500 days for the entire area and are over 900 days north of a line from Wausau to Iron Mountain. Any values over 400 signal potential for sufficiently thick ice for break up ice jams, given there is sufficient flow on the rivers. At this point, there is a medium risk of break up ice jamming on area rivers this season. The potential for ice jams generally increases with heavy rainfall events before the ice is out of the river system. ...Weather/climate outlook... There is an increased risk of below normal temperatures through the end of February and into the first portion of March. After the recent active weather, there is an enhanced risk of below normal precipitation late February into early March. Looking further ahead, for the March through May period, there is no clear signal for whether above normal or below normal temperatures will occur. There is a slight chance for above normal precipitation during this period. In Table 1 below, the current (CS) and historical (HS) or normal probabilities of exceeding Minor...Moderate...And Major flood stage 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. ...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 -------- ----- ----- ----- : --- --- --- --- --- --- :WISCONSIN RIVER MERRILL 11.0 13.5 15.0 : 6 22 <5 <5 <5 <5 ROTHSCHILD 25.0 27.0 28.0 : 8 21 <5 8 <5 6 :YELLOW RIVER BABCOCK 12.0 15.5 17.0 : 65 82 15 21 <5 8 :WISCONSIN RIVER WISCONSIN RAPIDS 12.0 13.5 14.5 : <5 11 <5 <5 <5 <5 :OCONTO RIVER OCONTO 9.0 12.0 14.0 : 13 24 <5 <5 <5 <5 :UPPER WOLF RIVER LANGLADE 11.5 12.5 14.0 : <5 <5 <5 <5 <5 <5 :WOLF RIVER SHIOCTON 11.0 13.5 15.0 : 61 44 9 5 <5 <5 NEW LONDON 9.0 10.5 11.1 : 65 55 10 6 <5 <5 :LITTLE WOLF RIVER ROYALTON 5.0 8.0 10.0 : 28 40 <5 <5 <5 <5 :WAUPACA RIVER WAUPACA 6.0 7.5 9.0 : <5 8 <5 <5 <5 <5 :FOX RIVER APPLETON 8.4 9.0 10.5 : <5 <5 <5 <5 <5 <5 :MENOMINEE RIVER FLORENCE 9.0 11.0 13.0 : 18 37 <5 14 <5 <5 NIAGARA 13.0 15.0 16.0 : 13 32 <5 14 <5 <5 VULCAN 15.0 17.0 19.0 : 8 25 <5 6 <5 <5 MCALLISTER 15.0 18.0 19.0 : 28 52 <5 14 <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: 02/17/2025 - 05/18/2025 LOCATION 95% 90% 75% 50% 25% 10% 5% -------- ------ ------ ------ ------ ------ ------ ------ :WISCONSIN RIVER MERRILL 6.5 6.9 7.4 8.2 9.2 10.2 11.1 ROTHSCHILD 17.8 18.5 19.5 20.9 22.6 24.4 25.8 :YELLOW RIVER BABCOCK 7.2 8.2 11.2 13.0 14.7 16.0 16.8 :WISCONSIN RIVER WISCONSIN RAPIDS 5.4 5.7 6.5 7.5 8.7 10.5 11.5 :OCONTO RIVER OCONTO 6.5 6.6 7.1 7.7 8.4 9.5 10.0 :UPPER WOLF RIVER LANGLADE 8.5 8.6 8.8 8.9 9.2 9.4 9.6 :WOLF RIVER SHIOCTON 9.0 9.5 10.4 11.4 12.4 13.4 14.1 NEW LONDON 7.8 8.2 8.8 9.3 10.1 10.5 10.8 :LITTLE WOLF RIVER ROYALTON 3.2 3.3 3.7 4.5 5.1 6.0 6.5 :WAUPACA RIVER WAUPACA 2.8 2.9 3.6 4.5 5.1 5.5 5.7 :FOX RIVER APPLETON 6.4 6.6 6.8 7.4 7.9 7.9 7.9 :MENOMINEE RIVER FLORENCE 5.4 5.7 6.5 7.3 8.4 9.9 10.6 NIAGARA 8.0 8.5 9.3 10.3 11.6 13.3 14.2 VULCAN 8.4 9.0 10.0 11.0 12.8 14.4 15.6 MCALLISTER 11.8 12.3 12.9 13.6 15.1 16.5 17.3 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: 02/17/2025 - 05/18/2025 LOCATION 95% 90% 75% 50% 25% 10% 5% -------- ------ ------ ------ ------ ------ ------ ------ :WISCONSIN RIVER MERRILL 1.3 1.2 1.2 1.1 1.1 1.1 1.1 ROTHSCHILD 1.4 1.4 1.3 1.3 1.2 1.2 0.9 :YELLOW RIVER BABCOCK 0.0 0.0 0.0 0.0 0.0 0.0 0.0 :WISCONSIN RIVER WISCONSIN RAPIDS 0.2 0.2 0.2 0.2 0.2 0.2 0.2 :OCONTO RIVER OCONTO 0.3 0.3 0.3 0.3 0.3 0.3 0.3 :UPPER WOLF RIVER LANGLADE 0.2 0.2 0.2 0.2 0.2 0.2 0.2 :WOLF RIVER SHIOCTON 0.8 0.8 0.7 0.7 0.7 0.7 0.7 NEW LONDON 1.1 1.1 1.1 1.0 1.0 1.0 1.0 :LITTLE WOLF RIVER ROYALTON 0.2 0.2 0.2 0.2 0.2 0.2 0.2 :WAUPACA RIVER WAUPACA 0.2 0.2 0.2 0.2 0.2 0.2 0.2 :FOX RIVER APPLETON 3.0 3.0 2.9 2.2 0.8 0.0 0.0 :MENOMINEE RIVER FLORENCE 0.4 0.4 0.4 0.4 0.4 0.4 0.4 NIAGARA 0.6 0.6 0.6 0.6 0.6 0.6 0.6 VULCAN 0.7 0.7 0.7 0.7 0.7 0.7 0.7 MCALLISTER 1.3 1.3 1.3 1.3 1.3 1.3 1.3 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 National Water Prediction Service. Visit our web site at weather.gov/grb for more weather and water information. The next outlook will be provided on Thursday February 27th, 2025.
...Spring Flood Outlook for Central and Northeast Wisconsin... The overall flood risk this spring is NEAR TO SLIGHTLY BELOW AVERAGE. This outlook references information from the following partners including: the United States Geological Survey (USGS), the U.S. Army Corps of Engineers, Regional Climate Centers, U.S. Drought Monitor, the Climate Prediction Center and NOAA Office of Water Prediction. This is the second of three spring flood outlooks. The third and final outlook will be provided on Thursday March 13th, 2025. Flood outlook factors... ...Snow Depth and Snow Water Equivalent... Even with the snow that has occurred since the last outlook, snow depths are normal to below normal while snow water equivalent is well below normal. Much of the recent snow has melted over much of central and northeast Wisconsin. Both of these factors related to snow on the ground continue to decrease the overall flood risk. ...Soil moisture and Frost Depths... Soil moisture values across the area remain around normal. There is also an area of below normal soil moisture in northern Wisconsin, where moderate drought (D1) persists. Overall, the lack of snowfall this winter will allow for more moisture to be absorbed into the soils and will generally decrease the flood risk. Frost depths at current is normal to above normal for this time of year. This is due to the frequent cold snaps that have occurred through the winter. Frost depths range from 15 inches to as deep as 39 inches, which is similar to the last outlook issued. The frost depth is much deeper than was observed at this time last year. The deeper frost depth may result in increased runoff as the more frozen ground will not allow water to readily pass through the surface. This is one of the main factors that increases the flood risk. ...River Ice and Streamflow Conditions... The frequent cold snaps this winter up to this point have led to thicker ice on area rivers. This shows up as freezing degree days that are already observed over 900 days for the entire area and are over 1300 days north of a line from Wausau to Iron Mountain. Values over 400 signal potential for sufficiently thick ice for break up ice jams. At current, there is an increased risk of ice jams on some of the rivers and some minor ice jams have been observed. The potential for ice jams will remain elevated with heavy rainfall events before the ice is completely flushed out of the rivers. Streamflows vary from normal to above normal, which is an increase compared to the last outlook. Areas of above normal are located across portions of the Wolf River and Upper Fox River basins. Otherwise, streamflows are near normal over the rest of northern and northeast WI. Where streamflows are elevated, there will be a slight increase to the overall flood risk. ...Lake Michigan Water Levels... Lake Michigan water levels continue to run slightly above normal which has been the case the past three years. This level will allow for decreased flooding impacts this season. For a comparison of impacts, there were very few impacts in 2022 through 2024, and Lake Michigan levels are slightly lower this year. ...Weather Outlook... After a dip in temperatures this weekend, plan on another period of above normal temperatures for the first week of March. There is also an opportunity for widespread rain and even some snow in the Tuesday and Wednesday time frame. Beyond next week, temperatures are expected to lean above average while precipitation will be above to possibly above average for the middle of March. Looking farther ahead, precipitation is still expected to lean above average for the rest of spring, for April through June. There still is no clear signal for above normal or below normal temperatures during this time. In Table 1 below, the current (CS) and historical (HS) or normal probabilities of exceeding Minor...Moderate...And Major flood stage 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. ...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 -------- ----- ----- ----- : --- --- --- --- --- --- :WISCONSIN RIVER MERRILL 11.0 13.5 15.0 : 5 24 <5 <5 <5 <5 ROTHSCHILD 25.0 27.0 28.0 : 6 21 <5 8 <5 6 :YELLOW RIVER BABCOCK 12.0 15.5 17.0 : 52 82 11 22 <5 7 :WISCONSIN RIVER WISCONSIN RAPIDS 12.0 13.5 14.5 : <5 11 <5 <5 <5 <5 :OCONTO RIVER OCONTO 9.0 12.0 14.0 : 8 24 <5 <5 <5 <5 :UPPER WOLF RIVER LANGLADE 11.5 12.5 14.0 : <5 <5 <5 <5 <5 <5 :WOLF RIVER SHIOCTON 11.0 13.5 15.0 : 38 44 <5 5 <5 <5 NEW LONDON 9.0 10.5 11.1 : 50 55 <5 6 <5 <5 :LITTLE WOLF RIVER ROYALTON 5.0 8.0 10.0 : 20 28 <5 <5 <5 <5 :WAUPACA RIVER WAUPACA 6.0 7.5 9.0 : <5 <5 <5 <5 <5 <5 :FOX RIVER APPLETON 8.4 9.0 10.5 : <5 <5 <5 <5 <5 <5 :MENOMINEE RIVER FLORENCE 9.0 11.0 13.0 : 18 37 <5 14 <5 <5 NIAGARA 13.0 15.0 16.0 : 12 32 <5 14 <5 5 VULCAN 15.0 17.0 19.0 : 10 25 <5 6 <5 <5 MCALLISTER 15.0 18.0 19.0 : 24 53 <5 14 <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: 03/03/2025 - 06/01/2025 LOCATION 95% 90% 75% 50% 25% 10% 5% -------- ------ ------ ------ ------ ------ ------ ------ :WISCONSIN RIVER MERRILL 6.6 7.0 7.4 8.0 9.0 9.6 11.0 ROTHSCHILD 17.8 18.4 19.2 20.7 21.9 23.4 25.3 :YELLOW RIVER BABCOCK 6.1 7.1 9.1 12.2 13.6 15.6 16.3 :WISCONSIN RIVER WISCONSIN RAPIDS 5.2 5.5 6.0 7.3 8.2 9.7 10.9 :OCONTO RIVER OCONTO 6.3 6.4 6.7 7.2 8.0 8.9 10.0 :UPPER WOLF RIVER LANGLADE 8.5 8.6 8.8 8.9 9.1 9.3 9.6 :WOLF RIVER SHIOCTON 8.6 9.1 9.8 10.6 11.7 12.8 13.1 NEW LONDON 7.3 8.0 8.5 9.0 9.5 10.0 10.2 :LITTLE WOLF RIVER ROYALTON 2.9 3.0 3.6 4.0 4.7 5.6 5.8 :WAUPACA RIVER WAUPACA 2.6 2.8 3.3 4.2 5.0 5.3 5.8 :FOX RIVER APPLETON 6.2 6.4 6.6 7.0 7.6 7.9 7.9 :MENOMINEE RIVER FLORENCE 5.5 6.1 6.8 7.5 8.5 10.2 10.6 NIAGARA 8.1 8.7 9.5 10.3 11.7 13.8 14.2 VULCAN 8.5 9.2 10.1 11.2 12.6 14.9 15.6 MCALLISTER 11.8 12.3 13.1 13.8 14.9 16.5 17.6 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% -------- ------ ------ ------ ------ ------ ------ ------ :WISCONSIN RIVER MERRILL 1.3 1.3 1.2 1.2 1.1 1.1 1.1 ROTHSCHILD 1.7 1.6 1.5 1.4 1.2 1.2 1.0 :YELLOW RIVER BABCOCK 0.0 0.0 0.0 0.0 0.0 0.0 0.0 :WISCONSIN RIVER WISCONSIN RAPIDS 0.5 0.4 0.4 0.3 0.3 0.3 0.3 :OCONTO RIVER OCONTO 0.7 0.6 0.5 0.5 0.4 0.4 0.4 :UPPER WOLF RIVER LANGLADE 0.3 0.3 0.3 0.3 0.2 0.2 0.2 :WOLF RIVER SHIOCTON 1.2 1.2 1.2 1.0 0.9 0.8 0.8 NEW LONDON 1.9 1.8 1.7 1.5 1.3 1.2 1.1 :LITTLE WOLF RIVER ROYALTON 0.3 0.3 0.3 0.3 0.2 0.2 0.2 :WAUPACA RIVER WAUPACA 0.3 0.3 0.3 0.2 0.2 0.2 0.2 :FOX RIVER APPLETON 3.9 3.2 2.4 1.1 0.0 0.0 0.0 :MENOMINEE RIVER FLORENCE 0.6 0.6 0.5 0.4 0.4 0.4 0.4 NIAGARA 0.8 0.8 0.8 0.6 0.6 0.6 0.5 VULCAN 0.9 0.9 0.9 0.8 0.7 0.7 0.7 MCALLISTER 1.5 1.5 1.4 1.4 1.2 1.2 1.1 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 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 National Water Prediction Service. Visit our web site at weather.gov/grb for more weather and water information. The third and final outlook will be provided on Thursday March 13th, 2025.
...THE 3RD 2025 SPRING FLOOD OUTLOOK FOR CENTRAL AND NORTHEAST WISCONSIN... The overall flood risk this spring is NEAR TO SLIGHTLY BELOW AVERAGE. This outlook references information from the following partners including: the United States Geological Survey (USGS), the U.S. Army Corps of Engineers, Regional Climate Centers, U.S. Drought Monitor, the Climate Prediction Center and NOAA Office of Water Prediction. Flood outlook factors... ...Snow Depth and Snow Water Equivalent... Overall, snowfall for the season (October-March 13) is running well below normal across much of the region. For most locations, it was one of the driest and one of the least snowiest January's on record. At Green Bay, there were only 2 days during the month where the snow depth was recorded at an inch or greater. The snow drought came to an end in February as colder than normal temperatures prevailed on most days between the 4th and 21st before well above normal temperatures quickly melted much of the snow during the last week of the month. Overall, snowfall for the month was at or above normal, with the greatest departures from normal across central into east-central Wisconsin. Due to the colder than normal temperatures, many of the snowfall events resulted in lower than normal water content. Due to the recent mild temperatures, as of March 13 the snow has melted across central, much of north-central and northeast Wisconsin. The only snow pack remaining was over far north-central Wisconsin, mainly across Vilas County where the snow depth remained from 2 to 8 inches. The remaining snow pack should melt fairly quickly this week due to the expected unseasonably mild temperatures. ...Soil moisture and Frost Depths... Entering the winter, soil moisture was below normal across northern Wisconsin due to ongoing drought conditions. The rest of the area saw near normal moisture. Top soil moisture returned closer to normal across the north due to the recent rain and snow over the past month. However, long term precipitation deficits continue to show Moderate Drought (D1) over northern Wisconsin. Soil moisture over the remainder of the area remained near normal as of mid March. Although snowfall was at or above normal in February, the snow was a fluffy type snow, resulting in low water content compared to normal. Despite the heavy rainfall and snowfall on March 4-5, much of the heavier rainfall ran off as the subsurface ground was still frozen during the event. Frost depths at current is normal to above normal for this time of year. This is due to the frequent cold snaps that have occurred through the winter. Frost depths range from 15 inches to as deep as 35 inches, which is similar to the last outlook issued. The frost depth is much deeper than was observed at this time last year due to the record warm winter. The deeper frost depth may result in increased runoff as the more frozen ground will not allow water to readily pass through the surface. This is one of the main factors that increases the flood risk. ...River Ice and Streamflow Conditions... The frequent cold snaps this winter up to this point have led to thicker ice on area rivers compared to the last few winters. This shows up as freezing degree days that are already observed over 900 days for the entire area and are over 1300 days north of a line from Wausau to Iron Mountain. Values over 400 signal potential for sufficiently thick ice for break up ice jams. At current, there is an increased risk of ice jams on some of the rivers and some minor ice jams have been observed. The potential for ice jams will remain elevated with heavy rainfall events before the ice is completely flushed out of the rivers. Streamflows vary from normal to above normal which is higher compared to the last outlook. Areas of above normal are located across portions of the Wolf River and Upper Fox River basins. Stream flows are above normal along the Wisconsin River in central Wisconsin. Otherwise, streamflows are near normal over the rest of northern and northeast WI. Where streamflows are elevated, there will be a slight increase to the overall flood risk. ...Lake Michigan Water Levels... Due to several dry periods over the last six months, Lake Michigan water levels are running slightly below the long term average, and over three and a half feet lower than at the record levels set in 2020. ...Weather Outlook... Temperatures and precipitation (rain/snow) are more likely to average above normal into early April. For the April-June period, there is no clear signal for above, below or near normal temperatures. There is a greater chance that precipitation will run above normal during this period. 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. ...Lake Michigan Water Levels... Due to several dry periods over the last six months, Lake Michigan water levels are running slightly below the long term average, and over three and a half feet lower than at the record levels set in 2020. ...Weather Outlook... Temperatures and precipitation (rain/snow) are more likely to average above normal into early April. For the April-June period, there is no clear signal for above, below or near normal temperatures. There is a greater chance that precipitation will run above normal during this period. 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 at weather.gov/grb for more weather and water information. This is the last spring flood outlook for 2025. 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: 03/17/2025 - 06/15/2025 : 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 -------- ----- ----- ----- : --- --- --- --- --- --- :WISCONSIN RIVER MERRILL 11.0 13.5 15.0 : <5 24 <5 <5 <5 <5 ROTHSCHILD 25.0 27.0 28.0 : <5 21 <5 8 <5 6 :YELLOW RIVER BABCOCK 12.0 15.5 17.0 : 38 74 8 20 <5 6 :WISCONSIN RIVER WISCONSIN RAPIDS 12.0 13.5 14.5 : <5 11 <5 <5 <5 <5 :OCONTO RIVER OCONTO 9.0 12.0 14.0 : 9 24 <5 <5 <5 <5 :UPPER WOLF RIVER LANGLADE 11.5 12.5 14.0 : <5 <5 <5 <5 <5 <5 :WOLF RIVER SHIOCTON 11.0 13.5 15.0 : 27 46 <5 5 <5 <5 NEW LONDON 9.0 10.5 11.1 : 39 56 <5 6 <5 <5 :LITTLE WOLF RIVER ROYALTON 5.0 8.0 10.0 : 18 30 <5 <5 <5 <5 :WAUPACA RIVER WAUPACA 6.0 7.5 9.0 : <5 <5 <5 <5 <5 <5 :FOX RIVER APPLETON 8.4 9.0 10.5 : <5 <5 <5 <5 <5 <5 :MENOMINEE RIVER FLORENCE 9.0 11.0 13.0 : 23 37 <5 14 <5 <5 NIAGARA 13.0 15.0 16.0 : 8 32 <5 14 <5 5 VULCAN 15.0 17.0 19.0 : <5 25 <5 6 <5 <5 MCALLISTER 15.0 18.0 19.0 : 22 53 <5 14 <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: 03/17/2025 - 06/15/2025 LOCATION 95% 90% 75% 50% 25% 10% 5% -------- ------ ------ ------ ------ ------ ------ ------ :WISCONSIN RIVER MERRILL 7.0 7.0 7.0 7.4 8.3 9.3 10.3 ROTHSCHILD 18.1 18.1 18.1 19.3 20.6 22.9 24.4 :YELLOW RIVER BABCOCK 6.5 6.7 8.1 10.7 12.9 15.2 15.8 :WISCONSIN RIVER WISCONSIN RAPIDS 5.1 5.1 5.4 6.4 7.4 8.8 9.8 :OCONTO RIVER OCONTO 6.2 6.3 6.5 7.1 7.8 8.8 9.3 :UPPER WOLF RIVER LANGLADE 8.6 8.6 8.7 8.8 9.1 9.3 9.5 :WOLF RIVER SHIOCTON 9.6 9.6 9.7 10.4 11.1 11.9 12.2 NEW LONDON 8.2 8.2 8.2 8.8 9.3 9.8 9.8 :LITTLE WOLF RIVER ROYALTON 2.8 3.1 3.5 4.0 4.8 5.4 6.0 :WAUPACA RIVER WAUPACA 2.6 2.7 3.4 4.3 4.9 5.5 5.6 :FOX RIVER APPLETON 6.7 6.7 6.8 7.1 7.5 7.9 7.9 :MENOMINEE RIVER FLORENCE 6.2 6.4 6.7 7.5 8.6 9.5 10.2 NIAGARA 9.0 9.1 9.4 10.3 12.1 12.8 13.6 VULCAN 9.7 9.8 10.0 10.9 12.6 13.9 14.6 MCALLISTER 12.7 12.8 12.9 13.6 14.8 15.9 16.4 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: 03/17/2025 - 06/15/2025 LOCATION 95% 90% 75% 50% 25% 10% 5% -------- ------ ------ ------ ------ ------ ------ ------ :WISCONSIN RIVER MERRILL 1.9 1.8 1.7 1.4 1.2 1.2 1.0 ROTHSCHILD 2.9 2.4 2.1 1.6 1.2 1.1 0.7 :YELLOW RIVER BABCOCK 0.0 0.0 0.0 0.0 0.0 0.0 0.0 :WISCONSIN RIVER WISCONSIN RAPIDS 3.6 3.3 0.4 0.3 0.2 0.2 0.2 :OCONTO RIVER OCONTO 0.7 0.6 0.5 0.4 0.4 0.4 0.3 :UPPER WOLF RIVER LANGLADE 0.4 0.4 0.3 0.3 0.3 0.2 0.2 :WOLF RIVER SHIOCTON 1.4 1.3 1.1 0.9 0.9 0.8 0.8 NEW LONDON 2.0 1.8 1.6 1.3 1.2 1.1 1.1 :LITTLE WOLF RIVER ROYALTON 0.3 0.3 0.3 0.2 0.2 0.2 0.2 :WAUPACA RIVER WAUPACA 0.3 0.3 0.3 0.2 0.2 0.2 0.2 :FOX RIVER APPLETON 4.1 3.3 2.2 0.9 0.0 0.0 0.0 :MENOMINEE RIVER FLORENCE 1.2 1.2 1.1 1.0 1.0 1.0 0.9 NIAGARA 1.8 1.7 1.7 1.6 1.5 1.3 1.3 VULCAN 2.3 2.2 2.1 1.9 1.7 1.6 1.5 MCALLISTER 3.5 3.3 3.0 2.7 2.4 2.2 2.2 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. VISIT OUR WEB SITE WEATHER.GOV/GRB FOR MORE WEATHER AND WATER INFORMATION.
References
River Levels
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