####018013817#### FGUS73 KLOT 261815 ESFLOT ILC007-011-031-037-063-075-089-091-093-097-099-103-105-111- 141-197-201-INC073-089-111-127-271700-280000- PROBABILISTIC HYDROLOGIC OUTLOOK NATIONAL WEATHER SERVICE Chicago/Romeoville IL 110 PM CDT Tue Mar 26 2024 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: 04/01/2024 - 06/30/2024 : 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 -------- ----- ----- ----- : --- --- --- --- --- --- :Pecatonica River Shirland 12.0 14.0 15.5 : 18 26 <5 8 <5 <5 :Rock River Rockton 10.0 11.0 14.0 : 17 30 12 22 <5 7 Latham Park 9.0 11.0 13.5 : 18 31 9 15 <5 7 Rockford (Auburn 6.0 8.5 10.0 : <5 9 <5 <5 <5 <5 :Kishwaukee River Belvidere 9.0 10.0 12.0 : 9 14 <5 6 <5 <5 :SB Kishwaukee River DeKalb 10.0 11.0 12.5 : 6 8 <5 <5 <5 <5 :Kishwaukee River Perryville 12.0 18.0 22.0 : 25 34 <5 <5 <5 <5 :Rock River Byron 13.0 14.0 16.0 : 14 19 10 16 <5 6 Dixon 16.0 18.0 20.0 : 11 15 <5 7 <5 <5 :North Branch Chicago River Chicago (Pulaski 18.0 20.0 21.0 : <5 <5 <5 <5 <5 <5 :Des Plaines River Russell 7.0 9.0 10.0 : 24 22 5 7 <5 <5 Gurnee 7.0 9.0 11.0 : 27 31 5 7 <5 <5 Lincolnshire 12.5 14.0 15.5 : 15 19 7 9 <5 5 Des Plaines 15.0 18.0 19.0 : 25 28 <5 6 <5 <5 River Forest 16.0 17.5 18.5 : <5 <5 <5 <5 <5 <5 Riverside 7.5 8.0 9.0 : 17 18 7 8 <5 <5 Lemont 10.0 13.0 15.0 : 48 46 <5 <5 <5 <5 :WB Du Page River Warrenville 11.5 14.5 17.5 : 16 17 <5 <5 <5 <5 :East Branch Du Page River Bolingbrook 20.0 22.0 24.0 : <5 <5 <5 <5 <5 <5 :Du Page River Plainfield 12.0 14.0 15.0 : <5 <5 <5 <5 <5 <5 Shorewood 15.5 17.5 19.5 : 32 30 9 9 <5 <5 :Fox River Algonquin Lock & 9.5 10.5 12.0 : 37 41 15 23 8 12 Montgomery 13.5 15.0 16.0 : 8 14 <5 <5 <5 <5 Dayton 12.0 14.0 24.0 : 40 45 15 18 <5 <5 :Kankakee River Dunns Bridge 10.0 12.0 13.0 : 11 18 <5 <5 <5 <5 Shelby 10.5 11.5 12.5 : 32 40 13 19 8 10 Momence 5.0 6.5 9.0 : 23 27 11 9 <5 <5 :Iroquois River Rensselaer 12.0 14.0 15.0 : 25 26 7 8 7 7 Foresman 18.0 22.0 24.0 : 28 30 <5 <5 <5 <5 Iroquois 18.0 24.0 25.0 : 50 61 <5 <5 <5 <5 :Sugar Creek Milford 18.0 22.0 26.0 : 55 57 14 15 <5 <5 :Iroquois River Chebanse 16.0 18.0 20.0 : 11 9 <5 <5 <5 <5 :Kankakee River Wilmington 6.5 8.0 10.0 : 17 15 6 7 <5 <5 :Mazon River Coal City 12.0 16.0 19.0 : 18 19 <5 <5 <5 <5 :Vermilion River Pontiac 14.0 15.0 18.0 : 10 10 8 7 <5 <5 Leonore 16.0 21.0 26.0 : 26 30 8 10 <5 <5 :Hart Ditch Dyer 12.0 13.0 14.0 : <5 <5 <5 <5 <5 <5 :Thorn Creek Thornton 9.0 14.0 15.5 : 22 21 <5 <5 <5 <5 :Little Calumet River Munster (Hohman A 12.0 14.0 17.0 : 50 49 21 21 9 9 South Holland 16.5 18.0 20.0 : <5 <5 <5 <5 <5 <5 :Illinois River Morris 16.0 18.0 22.0 : 30 30 17 17 8 8 Ottawa 463.0 467.0 471.0 : 30 31 12 13 <5 <5 La Salle 20.0 27.0 31.0 : 73 72 13 15 <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: 04/01/2024 - 06/30/2024 Location 95% 90% 75% 50% 25% 10% 5% -------- ------ ------ ------ ------ ------ ------ ------ :Pecatonica River Shirland 6.3 6.5 8.0 9.5 11.4 12.7 13.4 :Rock River Rockton 5.4 5.6 6.3 7.6 9.1 11.7 12.8 Latham Park 5.3 5.4 5.8 6.9 8.2 10.9 12.2 Rockford (Auburn 3.0 3.0 3.0 3.1 3.5 4.9 5.9 :Kishwaukee River Belvidere 2.3 3.0 3.9 5.6 7.6 8.9 9.9 :SB Kishwaukee River DeKalb 3.9 4.3 5.4 7.0 8.1 9.8 10.4 :Kishwaukee River Perryville 7.0 7.5 8.3 10.0 12.0 13.4 14.9 :Rock River Byron 7.1 7.4 8.3 10.0 11.1 14.0 15.2 Dixon 9.3 9.5 10.2 11.7 12.9 16.2 17.2 :North Branch Chicago River Chicago (Pulaski 12.7 13.0 13.8 14.9 15.9 16.9 17.5 :Des Plaines River Russell 4.2 4.5 5.3 6.3 7.0 7.8 9.1 Gurnee 3.3 3.7 4.7 6.0 7.1 8.2 9.3 Lincolnshire 7.8 7.9 9.2 10.3 11.7 13.5 14.8 Des Plaines 9.8 10.1 12.3 13.5 15.0 16.9 17.9 River Forest 6.8 7.5 9.8 11.5 13.0 14.3 15.0 Riverside 3.8 4.2 5.0 6.4 7.0 7.8 8.1 Lemont 7.3 7.7 8.7 9.9 10.6 11.6 11.7 :WB Du Page River Warrenville 8.9 9.2 9.7 10.8 11.2 11.8 11.9 :East Branch Du Page River Bolingbrook 16.6 16.8 17.6 18.4 18.8 19.4 19.6 :Du Page River Plainfield 8.2 8.3 9.1 10.0 10.6 11.1 11.6 Shorewood 11.9 12.2 12.9 13.9 15.3 16.5 17.2 :Fox River Algonquin Lock & 6.8 7.2 8.1 9.2 10.2 11.4 12.5 Montgomery 11.9 12.2 12.5 12.8 13.2 13.5 13.6 Dayton 7.6 8.2 9.7 11.3 12.8 14.9 16.0 :Kankakee River Dunns Bridge 4.8 5.7 7.3 8.2 9.6 10.1 10.4 Shelby 6.5 6.9 8.7 9.7 10.7 11.8 13.8 Momence 2.5 3.0 3.5 4.1 4.9 6.7 8.1 :Iroquois River Rensselaer 6.3 7.7 8.7 10.2 12.0 13.1 16.8 Foresman 11.0 12.6 14.5 16.2 18.3 19.6 22.0 Iroquois 11.3 12.8 15.6 18.0 20.7 22.5 23.3 :Sugar Creek Milford 9.7 13.5 16.6 18.4 20.0 22.7 24.7 :Iroquois River Chebanse 7.1 8.9 9.7 11.8 15.1 16.0 17.0 :Kankakee River Wilmington 2.6 3.1 3.8 5.0 5.7 7.1 8.6 :Mazon River Coal City 3.5 5.0 7.4 9.8 11.5 13.7 14.5 :Vermilion River Pontiac 5.1 5.9 7.2 9.1 11.3 13.9 17.0 Leonore 7.4 9.0 11.1 13.6 16.6 20.1 22.7 :Hart Ditch Dyer 3.9 4.1 5.2 6.0 6.9 8.6 11.7 :Thorn Creek Thornton 4.7 5.3 6.3 7.5 8.8 10.4 13.1 :Little Calumet River Munster (Hohman A 9.7 10.3 11.1 11.9 13.4 16.4 19.8 South Holland 9.3 10.0 11.2 12.6 14.0 14.9 16.1 :Illinois River Morris 6.7 8.4 10.5 13.9 16.4 21.3 23.7 Ottawa 459.0 459.2 460.1 461.8 463.6 467.7 469.9 La Salle 13.3 16.1 19.5 22.9 24.7 28.7 30.9 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: 04/01/2024 - 06/30/2024 Location 95% 90% 75% 50% 25% 10% 5% -------- ------ ------ ------ ------ ------ ------ ------ :Pecatonica River Shirland 6.0 5.8 5.2 4.6 4.3 3.8 3.8 :Rock River Rockton 5.2 4.9 4.1 3.5 3.1 2.9 2.8 Latham Park 5.2 5.0 4.7 4.4 4.2 4.0 4.0 Rockford (Auburn 2.9 2.9 2.7 2.5 2.4 2.3 2.3 :Kishwaukee River Belvidere 1.8 1.7 1.6 1.4 1.2 1.0 0.9 :SB Kishwaukee River DeKalb 3.2 3.2 3.1 3.1 3.0 2.9 2.8 :Kishwaukee River Perryville 6.1 6.0 5.9 5.7 5.5 5.3 5.2 :Rock River Byron 7.0 6.7 6.1 5.7 5.3 5.1 5.0 Dixon 9.2 8.9 8.4 8.1 7.8 7.5 7.5 :North Branch Chicago River Chicago (Pulaski 11.1 11.1 11.0 10.9 10.8 10.7 10.7 :Des Plaines River Russell 2.7 2.7 2.5 2.3 2.1 1.8 1.6 Gurnee 2.1 2.0 1.8 1.5 1.3 1.0 0.9 Lincolnshire 6.7 6.6 6.4 6.2 6.0 5.8 5.7 Des Plaines 8.5 8.4 8.3 8.1 7.9 7.6 7.6 River Forest 4.2 4.1 3.8 3.3 2.8 2.3 2.2 Riverside 2.4 2.3 2.2 2.0 1.7 1.5 1.4 Lemont 5.8 5.7 5.5 5.3 5.0 4.8 4.7 :WB Du Page River Warrenville 7.6 7.5 7.5 7.5 7.3 7.3 7.3 :East Branch Du Page River Bolingbrook 14.5 14.5 14.4 14.3 14.2 14.2 14.1 :Du Page River Plainfield 6.9 6.8 6.8 6.7 6.7 6.6 6.6 Shorewood 10.4 10.3 10.2 10.2 10.1 10.0 10.0 :Fox River Algonquin Lock & 5.9 5.7 5.5 5.1 4.8 4.6 4.5 Montgomery 11.5 11.5 11.4 11.2 11.1 11.0 11.0 Dayton 6.6 6.4 6.1 5.8 5.5 5.1 5.1 :Kankakee River Dunns Bridge 4.1 3.9 3.6 3.4 3.1 2.8 2.5 Shelby 5.7 5.5 5.1 4.8 4.5 4.2 4.0 Momence 2.1 2.0 1.8 1.7 1.6 1.5 1.4 :Iroquois River Rensselaer 4.4 4.4 4.2 3.9 3.7 3.4 3.1 Foresman 6.6 6.5 6.0 5.6 5.2 4.7 4.2 Iroquois 6.8 6.5 6.0 5.3 4.7 3.9 3.3 :Sugar Creek Milford 3.8 3.7 3.5 3.3 3.1 2.4 2.4 :Iroquois River Chebanse 4.1 4.0 3.7 3.4 3.2 2.9 2.4 :Kankakee River Wilmington 1.9 1.8 1.7 1.6 1.5 1.3 1.2 :Mazon River Coal City 1.8 1.7 1.6 1.4 1.0 0.5 0.5 :Vermilion River Pontiac 3.3 3.3 3.2 3.0 2.9 2.0 1.9 Leonore 4.2 4.1 4.0 3.8 3.5 3.0 2.1 :Hart Ditch Dyer 2.0 2.0 2.0 1.9 1.8 1.8 1.8 :Thorn Creek Thornton 2.8 2.8 2.8 2.7 2.6 2.6 2.6 :Little Calumet River Munster (Hohman A 5.7 5.6 5.5 5.4 5.3 5.3 5.2 South Holland 5.7 5.6 5.5 5.4 5.3 5.3 5.2 :Illinois River Morris 5.2 5.1 5.0 4.9 4.8 4.8 4.7 Ottawa 458.7 458.6 458.6 458.5 458.5 458.5 458.5 La Salle 12.0 11.8 11.5 11.1 10.9 10.8 10.6 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/lot for more weather and water information. The next outlook will be issued $$