Sioux Falls, South Dakota – Stronger winds and low humidity Sunday afternoon are increasing grassfire risk across southeast South Dakota, impacting travel corridors including I-29 and I-90.
According to the US National Weather Service in Sioux Falls, a warm and dry weekend pattern continues, with lighter winds Saturday limiting fire concerns before conditions intensify Sunday. Relative humidity is expected to fall between 20% and 35% Sunday afternoon, while wind gusts may reach 15 to 25 mph, strongest across south-central South Dakota.
Gregory County is under a Fire Weather Watch from noon to 6 p.m. CST Sunday, where humidity could drop near or below 25% with gusts potentially exceeding 25 mph. Near-critical fire weather conditions are possible in surrounding counties, particularly in open grassland areas.
Communities including Mitchell, Yankton, Chamberlain, Sioux Falls, Brookings, and areas along Interstate 90 and Interstate 29 may experience elevated fire danger during peak afternoon hours. Dry vegetation combined with wind-driven spread increases the risk of rapidly moving grassfires.
The National Weather Service urges residents to avoid outdoor burning and prevent sparks from equipment or vehicles. Even routine activities can ignite fires under dry and windy conditions.
The elevated fire risk may affect weekend travel, outdoor recreation, and agricultural operations across the region.
Conditions are expected to improve after sunset Sunday as humidity rises and winds gradually decrease.
