FNUS63 KFSD 201857 RFDFSD Rangeland Fire Danger Statement National Weather Service Sioux Falls SD 157 PM CDT Fri Mar 20 2026 ...RED FLAG WARNING IN EFFECT FROM 1 PM TO 10 PM CDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR AREAS ALONG THE MISSOURI RIVER... .DISCUSSION... Issued at 1214 PM CDT Fri Mar 20 2026 Temperatures will continue to rise near record values through Saturday afternoon. With very dry soils we're also expecting to see relative humidity values fall as low as 10 to 20% in areas along and south of I-90, with the lowest conditions near the Missouri River and Highway 20. The biggest variable of the fire weather forecast remains winds on Saturday. Latest guidance shows a narrow window after 1-2pm where a brief bout of 20-28 mph gusts may develop from south central SD eastward along the river for a few hours before subsiding early in the evening as a front moves closer. Feel given the degree of heating and potential mixing, will hedge closer to the 75/90th percentile of ensemble wind guidance which would suggest higher wind gusts at peak heating. The resultant GFDI values push the high to very high levels in areas south of I-90, but the extremely low RH may compensate for lower winds to still allow explosive fire growth to occur in fine fuels along the MO River. As a result, will issue a confined red flag warning for areas along the river. Future forecasts may make adjustments to areas of NW Iowa, where confidence on duration of highest potential is much lower than further west. Debris burning is the number one cause of wildfires...so please be careful with any use of fire. IAZ001-012-013-020-021-031-032-NEZ013-014-SDZ050-057>071-202200- Lyon-Sioux-O'Brien-Plymouth-Cherokee-Woodbury-Ida-Dixon-Dakota- Gregory-Brule-Aurora-Davison-Hanson-McCook-Minnehaha-Charles Mix- Douglas-Hutchinson-Turner-Lincoln-Bon Homme-Yankton-Clay-Union- OUTLOOK FOR SATURDAY AFTERNOON...The Grassland Fire Danger Index will reach the very high category. The grassland fire danger product reflects fire danger for native grasses. It is not intended for cured agricultural crops, nor will it reflect conditions in road ditches which have been mowed. $$ IAZ002-003-014-022-MNZ080-089-097-098-SDZ038-052>056-202200- Osceola-Dickinson-Clay-Buena Vista-Murray-Nobles-Pipestone-Rock- Beadle-Jerauld-Sanborn-Miner-Lake-Moody- OUTLOOK FOR SATURDAY AFTERNOON...The Grassland Fire Danger Index will reach the high category. The grassland fire danger product reflects fire danger for native grasses. It is not intended for cured agricultural crops, nor will it reflect conditions in road ditches which have been mowed. $$ MNZ071-072-081-090-SDZ039-040-202200- Lincoln-Lyon-Cottonwood-Jackson-Kingsbury-Brookings- OUTLOOK FOR SATURDAY AFTERNOON...The Grassland Fire Danger Index will reach the moderate category. The grassland fire danger product reflects fire danger for native grasses. It is not intended for cured agricultural crops, nor will it reflect conditions in road ditches which have been mowed. $$