Severe Weather Information

Severe weather, as defined for the purposes of this web page, include all storms occurring during spring, summer, and fall with damages that may result from excess rain, thunderstorms, lightning, hail, high winds, and tornadoes. Severe summer storms (hail, lightning/thunderstorm, or excess rain) are typically associated with unstable weather conditions and are not geographically predictable.  All portions of Clay County, the City of Irene, the City of Vermillion, and the Town of Wakonda are equally susceptible to these types of events, although the type and amount of damages will vary depending on the location.  For example, hail can result in significant agricultural damage in the rural parts of the county, but the urbanized area of Vermillion is more vulnerable to significant property damage due to having a higher density of population, housing, and commercial districts.

Similar to the other natural hazards identified, tornadoes and high winds have the potential to significantly impact the County. Based on historical information, the likelihood of tornadoes or high wind events occurring in any given year is less than the incidence of severe summer (hail, lightning/thunderstorm, or excess rain) or winter storms.  However, based on the nature of high wind and tornado events, they are likely to result in more damages than severe summer or winter storms.


Follow this link to download the 2023 Severe Weather Guide with tips and information about Summer Storms.


Clay Clay Storm Shelter Locations – Click on the shelter name to view a Google map of the location.


Public Warning Siren Tones

  • Steady Tone – Seek Shelter. Sirens are only used when the general public is in danger. The sirens in Vermillion and Wakonda are tested weekly on Mondays at Noon.

Public Warning Siren Activation Policy

  • Sirens will be activated for Tornado Warnings in the areas directly affected.
  • Sirens will be activated for imminent danger that require citizens to seek immediate shelter.
  • Sirens will be activated by official weather spotter request if they feel the situation is dangerous to the general public.
  • Sirens will be activated when the National Weather Service or The South Dakota Office of Emergency Management provides direct information of immediate danger.
  • Sirens will not be activated for Severe Thunderstorm Warnings.
  • Sirens will not be activated to issue an “all clear” once the danger has passed.

For questions concerning the siren activation policy, contact Layne Stewart @ 677.7185.