####018010380#### FGUS73 KDLH 131541 ESFDLH MNC001-017-021-031-035-061-071-075-115-137-WIC003-007-013-031- 051-099-113-129-150600- PROBABILISTIC HYDROLOGIC OUTLOOK NATIONAL WEATHER SERVICE Duluth MN 1100 AM CDT Thu Mar 13 2025 ...Spring Flood and Water Resources Outlook... This outlook covers NE Minnesota and NW Wisconsin for river forecast points on the headwaters of the Mississippi, Chippewa, St. Croix, and Rainy Rivers. ...Current Conditions... Most river basins have a normal to below normal amount of water in the snowpack. Some areas along the North Shore have normal to above normal snowwater. Drought conditions persist in the region due to well below normal precipitation since July. Fall rains slightly improved the drought condition in November. Precipitation since October 1st is near normal. The ground is deeply frozen due to frequent cold snaps and shallow snow depth. This is a key factor in this Spring's flood potential. Rivers are ice covered which could be a factor in ice jam flooding. Recent warm temperatures and strong winds have diminished snow pack across the region. While the headwaters of the Mississippi and Rainy basins have retained snow the Chippewa River headwaters are seeing some snow melt runoff. Rivers and streams feeding Lake Superior are displaying responses to snow melt runoff with many rivers showing water flowing over ice. The Knife River near Two Harbors is a good example. Melt is mainly occurring in the lower terrain along the North Shore. Active melt has been observed in all of northwest Wisconsin and areas south of Highway 2 in north central Minnesota. ...Short Term Outlook... The near term weather forecast shows a potent weather system moving into the region Friday March 14th and Saturday March 15th. Rain and thunderstorms are possible across central Wisconsin with snow across northwest Minnesota. Rainfall is expected over frozen ground that may lead to minor runoff troubles due to poorly drained areas and ponding. River flooding is not expected. ...Climate Outlook... The Climate Prediction Center's 2 week outlooks show above normal temperatures and near to above normal precipitation. The outlook for March, April and May show an equal chance of both temperatures and precipitation being above or below normal. ...Spring Flood Risk... The Spring flood risk is normal to below normal and highest in Northeast Minnesota. Precipitation and rate of melt through early spring while the ground is still frozen is one of the most important flood risk factors. Frost depths of 30 inches or deeper are common which is much deeper than normal. The presence of deep frost and its affect on spring runoff are not explicitly accounted for in the probability of flooding. Thick river ice is present in some area waterways. If this ice were lifted by strong river rises spring break up ice jams would be possible. A significant rainfall event would be needed to cause this scenario. Spring ice jam flooding is difficult to predict and can quickly develop into a very hazardous situation. 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 -------- ----- ----- ----- : --- --- --- --- --- --- :Prairie River Taconite 10.0 12.0 13.0 : <5 <5 <5 <5 <5 <5 :Mississippi River Aitkin 13.0 15.0 18.0 : 12 53 5 33 <5 7 Fort Ripley 10.5 12.5 26.0 : 12 43 <5 20 <5 <5 :St. Croix River Danbury 7.0 8.5 10.0 : <5 8 <5 <5 <5 <5 :Snake River Pine City 9.0 10.0 11.0 : <5 10 <5 5 <5 <5 :St. Louis River Scanlon 10.5 11.0 13.0 : <5 5 <5 <5 <5 <5 :Knife River Near Two Harbors 33.0 34.0 36.0 : <5 <5 <5 <5 <5 <5 :Nemadji River South of Superior 24.0 26.0 28.0 : <5 <5 <5 <5 <5 <5 :Tyler Forks Mellen 9.0 10.0 12.0 : 20 35 12 25 <5 5 :Bad River Near Odanah 16.0 18.0 20.0 : <5 <5 <5 <5 <5 <5 At Odanah 8.5 9.5 10.5 : <5 6 <5 <5 <5 <5 :South Kawishiwi River Ely 6.5 7.5 8.5 : 5 25 <5 12 <5 <5 :Little Fork River Little Fork 22.0 24.0 26.0 : <5 <5 <5 <5 <5 <5 :Vermilion River Crane Lake 14.0 16.0 18.0 : 6 14 <5 <5 <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% -------- ------ ------ ------ ------ ------ ------ ------ :Prairie River Taconite 4.3 4.4 4.5 5.1 6.4 7.7 8.6 :Mississippi River Aitkin 7.5 7.6 8.3 9.4 11.8 13.5 15.1 Fort Ripley 6.1 6.1 6.7 7.6 9.5 10.9 12.5 :St. Croix River Danbury 2.7 2.8 2.8 3.4 4.3 5.4 5.9 :Snake River Pine City 5.5 5.5 5.5 5.8 6.6 8.0 8.3 :St. Louis River Scanlon 5.3 5.3 5.8 6.7 7.7 8.7 9.5 :Knife River Near Two Harbors 27.7 27.9 28.2 28.6 29.2 30.3 31.3 :Nemadji River South of Superior 12.9 12.9 13.0 15.3 18.2 21.9 22.8 :Tyler Forks Mellen 7.2 7.2 7.3 7.5 8.6 10.1 10.7 :Bad River Near Odanah 7.4 7.4 7.4 7.5 8.4 11.5 12.6 At Odanah 4.7 4.7 4.7 4.8 5.5 6.8 7.3 :South Kawishiwi River Ely 4.3 4.5 4.8 5.2 5.7 6.3 6.5 :Little Fork River Little Fork 6.0 6.1 6.8 7.7 9.8 12.6 14.2 :Vermilion River Crane Lake 9.0 9.4 10.3 11.2 12.3 13.1 14.4 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% -------- ------ ------ ------ ------ ------ ------ ------ :Prairie River Taconite 0.2 0.2 0.2 0.1 0.1 0.1 0.1 :Mississippi River Aitkin 2.4 2.2 1.8 1.3 1.0 0.6 0.5 Fort Ripley 4.5 4.3 3.5 2.7 1.8 1.3 1.1 :St. Croix River Danbury 1.5 1.3 1.2 0.9 0.9 0.8 0.8 :Snake River Pine City 0.4 0.3 0.2 0.2 0.1 0.1 0.1 :St. Louis River Scanlon 1.9 1.8 1.5 1.3 1.1 1.0 1.0 :Knife River Near Two Harbors 0.0 0.0 0.0 0.0 0.0 0.0 0.0 :Nemadji River South of Superior 0.2 0.2 0.1 0.1 0.1 0.1 0.1 :Tyler Forks Mellen 0.0 0.0 0.0 0.0 0.0 0.0 0.0 :Bad River Near Odanah 0.3 0.3 0.2 0.2 0.1 0.1 0.1 At Odanah 0.6 0.5 0.5 0.4 0.3 0.3 0.3 :South Kawishiwi River Ely 0.2 0.2 0.2 0.2 0.2 0.1 0.1 :Little Fork River Little Fork 1.0 1.0 0.9 0.7 0.6 0.4 0.3 :Vermilion River Crane Lake 0.4 0.4 0.4 0.3 0.3 0.3 0.3 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/dlh for more weather and water information. For additional information on stream flow conditions for USGS locations please reference https://dashboard.waterdata.usgs.gov For additional information on stream flow conditions at MNDNR sites www.dnr.state.mn.us/waters/csg/index.html or www.climate.umn.edu/dow/weekly_stream_flow/stream_flow_weekly.asp For more information on climate outlooks reference www.cpc.ncep.noaa.gov This is the third and final issuance of the Spring Flood Outlook. $$ ####018013889#### FGUS73 KGRB 131543 ESFGRB WIC125-085-041-037-075-069-067-083-073-115-125-078-029-141-097- 135-087-061-009-137-139-015-071-190500- PROBABILISTIC HYDROLOGIC OUTLOOK NATIONAL WEATHER SERVICE GREEN BAY WI 1040 AM CDT THU MAR 13 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. $$