FGUS73 KFGF 241709 ESFFGF MNC005-007-027-029-051-057-069-077-087-089-107-111-113- 119-125-135-159-167-NDC003-005-017-019-027-035-039-063- 067-071-073-077-081-091-095-097-099-281200- Probabilistic Hydrologic Outlook National Weather Service Eastern Grand Forks ND 1209 PM CDT Thu Oct 24 2024 ...RED RIVER BASIN OUTLOOK FOR RIVER FLOOD POTENTIAL... This outlook covers the Red River of the North and its Minnesota and North Dakota tributaries. Probabilistic Hydrologic Outlooks now use 69 years (1949-2018) of past weather, temperature, and precipitation for the ensemble predictive hydrographs used in calculating the probabilities of exceeding a river level for the valid period of the outlook. Note: Table 3 provides non-exceedance probabilities of flow (rather than stage) for the October 2024 issuance. Outlook Schedule - The National Weather Service in Grand Forks, North Dakota will be providing the National Water Prediction Services (NWPS) Long-Range Probabilistic Hydrologic Outlooks for the Red River of the North and its Minnesota and North Dakota tributaries according to the following schedule: - Near the end of the month throughout the year, except for... - The Spring Flood and Water Resources Outlooks that will be issued at least twice a month during the spring snowmelt season beginning in mid-to-late February or early March. The following message has three river data sections: - The first (Table 1) gives the current and normal/historical chances of river locations reaching their minor, moderate, and major flood categories. - The second (Table 2) gives the current chances of river locations rising above the river stages listed. - The third (Table 3) gives the current chances of river locations falling below the river stages listed. 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. ...Table 1--Probabilities for Minor, Moderate, and Major Flooding... Valid Period: 10/28/2024 - 01/26/2025 : 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 -------- ------ ------ ------ : --- --- --- --- --- --- Red River of the North..... Wahpeton 11.0 13.0 15.0 : <5 <5 <5 <5 <5 <5 Hickson 30.0 34.0 38.0 : <5 <5 <5 <5 <5 <5 Fargo 18.0 25.0 30.0 : <5 9 <5 <5 <5 <5 Halstad 26.0 32.0 37.5 : <5 <5 <5 <5 <5 <5 Grand Forks 28.0 40.0 46.0 : <5 <5 <5 <5 <5 <5 Oslo 26.0 30.0 36.0 : <5 6 <5 <5 <5 <5 Drayton 32.0 38.0 42.0 : <5 <5 <5 <5 <5 <5 Pembina 39.0 44.0 49.0 : <5 <5 <5 <5 <5 <5 : 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 -------- ------ ------ ------ : --- --- --- --- --- --- Minnesota Tributaries..... Sabin 13.0 15.0 19.0 : <5 <5 <5 <5 <5 <5 Hawley 8.0 9.0 11.0 : <5 <5 <5 <5 <5 <5 Dilworth 13.0 20.0 26.0 : <5 9 <5 <5 <5 <5 Twin Valley 10.0 12.0 14.0 : <5 <5 <5 <5 <5 <5 Hendrum 20.0 28.0 32.0 : <5 <5 <5 <5 <5 <5 Shelly 14.0 20.0 23.0 : <5 <5 <5 <5 <5 <5 Climax 20.0 25.0 30.0 : <5 <5 <5 <5 <5 <5 High Landing 12.0 12.5 13.0 : <5 <5 <5 <5 <5 <5 Crookston 15.0 20.0 23.0 : <5 <5 <5 <5 <5 <5 Above Warren 67.0 71.0 75.0 : <5 <5 <5 <5 <5 <5 Alvarado 106.0 108.0 110.0 : <5 <5 <5 <5 <5 <5 Hallock 802.0 806.0 810.0 : <5 5 <5 <5 <5 <5 Roseau 16.0 18.0 19.0 : <5 <5 <5 <5 <5 <5 Note: The Roseau numbers consider the flow thru its diversion : 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 -------- ------ ------ ------ : --- --- --- --- --- --- North Dakota Tributaries..... Abercrombie 20.0 22.0 28.0 : <5 <5 <5 <5 <5 <5 Valley City 15.0 16.0 17.0 : <5 <5 <5 <5 <5 <5 Lisbon 15.0 17.0 19.0 : <5 <5 <5 <5 <5 <5 Kindred 16.0 19.0 20.5 : <5 <5 <5 <5 <5 <5 West Fargo Dvsn 18.0 20.0 21.0 : <5 <5 <5 <5 <5 <5 Harwood 84.0 86.0 91.0 : <5 <5 <5 <5 <5 <5 Enderlin 9.5 12.0 14.0 : <5 <5 <5 <5 <5 <5 Mapleton 18.0 21.0 23.0 : <5 <5 <5 <5 <5 <5 Hillsboro 10.0 13.0 16.0 : <5 <5 <5 <5 <5 <5 Minto 6.0 8.0 11.0 : <5 <5 <5 <5 <5 <5 Walhalla 11.0 16.0 18.0 : <5 <5 <5 <5 <5 <5 Neche 18.0 19.0 20.5 : <5 <5 <5 <5 <5 <5 LEGEND: CS = Conditional Simulation (outlook for current conditions) HS = Historical Simulation ( " " normal conditions) ft = feet (above gage zero datum) 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 at the locations listed. Interpretation Aid: The flood stage for Wahpeton on the Red River of the North is 11 feet. There is a 50 percent chance that it will rise above 5.4 feet and only a 10 percent chance that it will rise above 6.1 feet. ...Table 2--Exceedance Probabilities... Valid Period: 10/28/2024 - 01/26/2025 LOCATION 95% 90% 75% 50% 25% 10% 05% -------- ------ ------ ------ ------ ------ ------ ------ Red River of the North..... Wahpeton 5.4 5.4 5.4 5.4 5.4 6.1 6.9 Hickson 11.3 11.3 11.3 11.3 11.3 12.1 12.5 Fargo 14.8 14.8 14.8 14.8 14.8 15.3 15.6 Halstad 5.7 5.7 5.7 5.8 5.8 6.8 8.6 Grand Forks 16.2 16.2 16.2 16.2 16.5 17.0 18.2 Oslo 7.7 7.7 7.7 7.7 8.2 9.3 12.4 Drayton 12.5 12.5 12.5 12.5 12.8 13.5 15.1 Pembina 12.2 12.2 12.2 12.2 12.8 14.3 18.8 Minnesota Tribs: 95% 90% 75% 50% 25% 10% 05% -------- ------ ------ ------ ------ ------ ------ ------ South Fork Buffalo River..... Sabin 5.2 5.2 5.2 5.2 5.2 6.2 8.5 Buffalo River..... Hawley 3.3 3.3 3.3 3.4 3.5 4.2 4.8 Dilworth 3.7 3.7 3.7 3.7 3.9 5.0 7.5 Wild Rice River..... Twin Valley 2.1 2.1 2.1 2.1 2.1 3.1 4.5 Hendrum 2.4 2.4 2.4 2.4 2.7 5.8 9.9 Marsh River..... Shelly 4.0 4.0 4.0 4.0 4.0 4.0 4.3 Sand Hill River..... Climax 3.9 3.9 3.9 3.9 5.3 6.4 7.8 Red Lake River..... High Landing 2.8 2.8 2.8 2.8 2.9 3.6 4.4 Crookston 4.6 4.6 4.6 4.6 5.2 6.1 8.1 Snake River..... Above Warren 61.2 61.2 61.2 61.2 61.3 61.8 62.7 Alvarado 97.0 97.0 97.0 97.0 97.1 97.8 99.2 Two Rivers River..... Hallock 793.1 793.1 793.1 793.1 793.9 795.7 797.0 Roseau River..... considering the flow thru the Roseau diversion Roseau 5.6 5.6 5.6 5.6 5.6 6.5 6.8 North Dakota Tribs: 95% 90% 75% 50% 25% 10% 05% -------- ------ ------ ------ ------ ------ ------ ------ Wild Rice River..... Abercrombie 10.1 10.1 10.1 10.1 10.2 10.3 10.5 Sheyenne River..... Valley City 4.8 4.8 4.8 4.8 4.8 4.8 4.8 Lisbon 4.0 4.0 4.0 4.0 4.0 4.0 4.0 Kindred 4.4 4.4 4.4 4.4 4.4 4.4 4.4 West Fargo Dvsn 8.7 8.7 8.7 8.7 8.7 8.7 8.7 Harwood 70.1 70.1 70.1 70.1 70.1 70.1 70.5 Maple River..... Enderlin 2.0 2.0 2.0 2.0 2.0 2.0 2.0 Mapleton 7.9 7.9 7.9 7.9 7.9 7.9 7.9 Goose River..... Hillsboro 1.9 1.9 1.9 1.9 1.9 1.9 2.1 Forest River..... Minto 1.4 1.4 1.4 1.4 1.4 1.4 1.7 Pembina River..... Walhalla 2.1 2.1 2.1 2.1 2.1 2.1 2.4 Neche 3.1 3.1 3.1 3.1 3.1 3.3 3.8 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 at the locations listed. Interpretation Aid: Note Table 3 provides non-exceedance probabilities of flow (rather than stage) for the October 2024 issuance. There is a 75 percent chance that flow will be less than 0.3 kcfs at Wahpeton during the valid period. ...Table 3--Non-Exceedance Probabilities... Valid Period: 10/28/2024 - 01/26/2025 LOCATION 95% 90% 75% 50% 25% 10% 05% -------- ------ ------ ------ ------ ------ ------ ------ Red River of the North..... Wahpeton 0.4 0.4 0.3 0.3 0.3 0.3 0.3 Hickson 0.4 0.4 0.3 0.3 0.3 0.3 0.3 Fargo 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Halstad 0.9 0.8 0.7 0.7 0.7 0.7 0.7 Grand Forks 1.2 1.1 1.0 1.0 0.9 0.9 0.9 Oslo 1.2 1.1 1.0 1.0 1.0 0.9 0.9 Drayton 1.4 1.2 1.1 1.1 1.0 1.0 1.0 Pembina 1.4 1.3 1.2 1.1 1.1 1.1 1.1 Minnesota Tribs: 95% 90% 75% 50% 25% 10% 05% -------- ------ ------ ------ ------ ------ ------ ------ South Fork Buffalo River..... Sabin 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Buffalo River..... Hawley 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Dilworth 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Wild Rice River..... Twin Valley 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Hendrum 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Marsh River..... Shelly 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Sand Hill River..... Climax 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Red Lake River..... High Landing 0.1 0.1 0.1 0.1 0.0 0.0 0.0 Crookston 0.3 0.3 0.2 0.2 0.1 0.1 0.1 Snake River..... Above Warren 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Alvarado 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Two Rivers River..... Hallock 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Roseau River..... considering the flow thru the Roseau diversion Roseau 0.0 0.0 0.0 0.0 0.0 0.0 0.0 North Dakota Tribs: 95% 90% 75% 50% 25% 10% 05% -------- ------ ------ ------ ------ ------ ------ ------ Wild Rice River..... Abercrombie 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Sheyenne River..... Valley City 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Lisbon 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Kindred 0.1 0.1 0.1 0.1 0.1 0.1 0.1 West Fargo Dvsn 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Harwood 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Maple River..... Enderlin 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Mapleton 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Goose River..... Hillsboro 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Forest River..... Minto 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Pembina River..... Walhalla 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Neche 0.0 0.0 0.0 0.0 0.0 0.0 0.0 .THE OUTLOOK PRODUCTION PROCESS... This long-range probabilistic outlook is based on a series of peak river levels or crests taken from the forecast hydrograph results of the NWS Community Hydrologic Prediction System (CHPS). The model is run for multiple scenarios starting at current river, snow, and soil conditions using nearly 70 years of past precipitation and temperature conditions that were experienced for those past years during the timeframe of the outlook period. These crests can then be ranked from lowest to highest and assigned an exceedance probability. For example, for a series of 50 years, the lowest ranked crest has 49 crests above it. Since 95 percent of the crests are above it, it is assigned a 95 percent probability of exceedance (POE). A YouTube video on "How to Interpret River Outlook Products" is at: www.youtube.com/watch?v=pSoEgvsnpv4 The probabilities can be used for risk management by using them as an indication of the range of crests that may be expected during the valid period of the outlook. By providing a range of peak river level probabilities, the NWS is contributing to the area's Impact-Based Decision Support Services that help with long-range flood planning and response readiness. This outlook is a part of NOAA'S National Weather Service's National Water Prediction Services (NWPS). This outlook was produced using precipitation and temperatures for the years 1949 through 2018. .ADDITIONAL INFORMATION SOURCES... This outlook is also presented as graphs of the probability of stage exceedance for the full period and for weekly intervals during the period. These graphs, together with explanations that help in interpreting them, are available from the NWS Grand Forks NWPS web page at: www.weather.gov/grandforks or www.weather.gov/fgf then click on "Rivers and Lakes" above the map. Current river conditions for all river forecast points in the Red River of the North and Devils/Stump Lake basins are available on our web site. Also, 7-day deterministic forecasts will be issued at least once a day when river forecast locations will be at or above flood during that period. Refer to the separate Devils Lake Probabilistic Hydrologic Outlook for Devils and Stump Lakes probability of exceedance levels and low-water non-exceedance levels. If you have any questions, contact the NWS at 701-772-0720. You can follow us on Facebook at www.facebook.com/NWSGrandForks and on Twitter at @NWSGrandForks. $$ www.weather.gov/fgf NNNN