Nearly 900,000 people live in South Dakota. Many of these people have experienced natural disasters in the state firsthand or had to evacuate because of disasters. However, many South Dakotans don’t realize just how many types of natural disasters can occur in the state.
This analysis goes over what natural disasters occur in South Dakota, the worst natural disasters to hit the state since 2000, and what residents can do to prepare.
Is South Dakota At Risk of Natural Disasters?
Compared to the rest of the United States, South Dakota has a low risk of natural disasters. Excluding COVID, South Dakota has had 54 disaster declarations since 2000. Of these, 35 were declared major disasters.
South Dakota is also sometimes hit by natural disasters, which cause more than $1 billion in damages. Since 2000, more than 22 separate $1-billion events have affected South Dakota.
Worst Natural Disasters in South Dakota By Cost (Since 2000)
- 2012 Drought and Heat Wave: $39.3 billion
- 2022 Drought and Heat Wave: $22.2 billion
- Spring-Fall 2002 Drought: $15.1 billion
- Spring-Fall 2013 Drought and Heat Wave: $13.4 billion
- August 2020 Severe Weather-Derecho: $12.7 billion
Worst Natural Disasters in South Dakota By Deaths (Since 2000)
- 2021 Drought and Heat Wave: 229 deaths
- 2022 Drought and Heat Wave: 136 deaths
- 2012 Drought and Heat Wave: 123 deaths
- December 2022 Winter Storm and Cold Wave: 87 deaths
- Spring-Fall 2013 Drought and Heat Wave: 53 deaths
*Cost and death tolls are for the entire disaster, including in other states affected.
Most Common Natural Disasters in South Dakota
1. Heavy Snowfall and Winter Storms
South Dakota gets an average of 37 inches of snowfall per year, which ranks it #15 in the country for the most snowfall. However, these numbers are deceptive because some parts of South Dakota receive much more snowfall than others. The southwestern part of South Dakota gets the most snow, with some towns receiving more than 90 inches annually.
Snowfall in North Dakota often comes in the form of winter storms. Along with North Dakota and Nebraska, South Dakota is the most at-risk state in the country for blizzards.
The flat Plains area of South Dakota makes blizzards worse because there is nothing to block the wind. The climate of the Plains region means that snow is light and fluffy.
Because there is nothing to stop the wind in the flat landscape, snow easily blows into the air and can block visibility. People can get lost in the winter storms and get hypothermia and frostbite.
South Dakota can expect an average of two blizzards yearly, though some years have seen numerous blizzards.
South Dakota Winter Weather Stats
- Average snowfall per year: 37”
- Snowfall days per year: 51 days
- Coldest recorded temperature: -58°F in McIntosh in 1936
- Record snowfall: 47” in Deadwood in 1973
Winter Driving Fatalities
With 7.9 fatal crashes per 1 million drivers, South Dakota ranks #9 in the country for the most dangerous states for winter driving. The state is sparsely populated, so roads can take a long time to be cleared of snow.
2. Freeze Events
The climate of South Dakota makes it ideal for freezing rain. Some areas of South Dakota can expect approximately 6-9 hours of freezing rain per year.
Freezing rain most frequently occurs during December and January, but fall and spring freeze events also happen. Icy road conditions from the rain make vehicle accidents and slip and fall injuries common. It’s also common for people to lose power during freezing rain events, meaning that thousands can be left without a way to heat their homes during the coldest months.
Only a small portion of South Dakota is covered by forest. However, much of the state is covered by farmland or grasslands. The state often experiences drought, which means lots of dry grass that can easily ignite. South Dakota is a windy state, so fires can rapidly spread. Because of this, South Dakota is at very high risk for wildfires.
Since 2000, South Dakota has declared disaster 18 times because of wildfires and has been affected by 2 billion-dollar wildfires.
Because of climate change, the risk of wildfires in South Dakota is growing. By 2050, an estimated 80% of all properties in the state will be at risk of wildfire.
South Dakota Wildfire Stats
- Acres burned in 2021: 43,620
- Number of fires in 2021: 868
- Percentage of state covered by grasslands: 50%
- Number of properties currently at risk of wildfire: 502,922
4. Heat Waves and Droughts
As with the rest of the country, the risk of heat days is increasing in South Dakota. Currently, South Dakota averages 10 “dangerous” heat days per year. These are defined by the National Weather Service as days where the heat index is 103F or above. By 2050, the number of dangerous heat days in South Dakota is expected to increase to 35 days per year.
In addition to more dangerous heat days, South Dakota will also see more “Local Hot Days.” Local Hot Days are defined as “Days at or above the 98th percentile temperature, or the temperature than an area could expect to see on the hottest 7 days of the year.” Essentially, Local Hot Days factor in what temperatures a local population is used to experiencing.
An increase in Local Hot Days is associated with health problems like strokes, and heat-related deaths are more likely to occur. Energy demands also increase from air conditioning use.
All parts of South Dakota are expected to have an increase in Local Hot Days, but Custer County is particularly at-risk. By 2053, Custer is expected to have 17 consecutive days with temperatures at or above 91.6℉.
Droughts often accompany heat waves. As an agricultural state, droughts can be particularly devastating to South Dakota and take a large economic toll. They also increase the risk of wildfires.
Flooding is common in South Dakota and regularly occurs in some areas of the state, especially along the Missouri, Big Sioux, and Rapid Creek Rivers. Floods most commonly happen during spring when heavy rainfalls and snowmelt cause rivers to swell. Intense storms can also cause flash floods in South Dakota, particularly in the summertime.
South Dakota Flood Stats
- 62,500 properties at substantial risk in 2020
- 83,400 properties at risk by 2050
- 63,000 properties at substantial risk by 2050
- 17,700 properties at almost certain risk by 2050
- 13,100 FEMA flood damage claims since 2000
Which Areas of South Dakota Are Most At-Risk of Flooding?
Floods can occur in all parts of South Dakota, but some areas of the state are particularly at-risk. Below are the areas of South Dakota with the greatest percentage of properties likely to experience flooding (based on 2020 calculations).
- Sturgis: 40%
- Hot Springs: 22%
- Spearfish: 22%
- Box Elder: 20%
- Rapid City: 18%
- Rapid Valley: 17%
- Madison: 16%
- Pierre: 15%
- Watertown: 13%
- Aberdeen: 10%
South Dakota averages 30 tornadoes annually, but most of these are very weak. The state has not had an F5 tornado and only three F4 tornadoes in recent history. Since 2000, there have been no tornado-related deaths in North Dakota and just 9 injuries. Because the state is sparsely populated, tornadoes generally do not cause much property damage.
However, this doesn’t mean South Dakota residents shouldn’t be prepared for tornadoes. They should have a storm shelter and emergency radio with tornado alerts set so they can take cover quickly.
The Western part of South Dakota is located in “Hail Alley,” an area known for having many hail storms. From 2018 to 2021, South Dakota experienced an average of 319 hail events – which ranks it as #3 for number of hail events in the country. When it comes to hail damage per capita, South Dakota ranks #4 in the nation.
Hail in South Dakota can get very large. The largest hailstone ever recorded fell in Vivian, South Dakota, on July 23rd, 2010. The hailstone was 8 inches in diameter and weighed nearly 2 lbs.