The Frontenac Civil Defense is an organized body of volunteers that works in conjunction with the fire and police departments and is responsible for the protection of life and property in the event of natural disaster. Due to Frontenac's location in "Tornado Alley", the prime concern is collection and dissemination of information related to severe weather and tornadoes. Civil Defense volunteers are called out during severe weather events and are key in early notification of the public should severe weather be imminent. This storm season typically spans from March through October. Starting in early February, the city's storm sirens are tested on a weekly basis on Wednesday at noon.

The Frontenac Civil Defense is in the process of preparing a disaster preparation and response plan using lessons learned from disasters that have occurred in the region in the past few years. This plan may eventually include identifying private storm shelters that may be in use in the city. This part of the plan will require the public's help and will be kept confidential and only available to emergency responders following a natural disaster.