Johnson County IL in Illinois faces tornado / flash flooding risk across its 346 square mile area. Vienna serves this southern Illinois county near the Shawnee National Forest. Johnson serves as the county seat and regional emergency coordination hub.
// Preparedness Recommendations
- Evacuation routes inland should be identified in advance.
- Store at least 72 hours of food and water.
- Elevate critical belongings above flood level.
- Have backup power ready in case of grid failure.
// Recommended Supplies
Essential gear for power outages, severe weather, and emergency situations in your area.
- Emergency Food Supplies
- Water Filtration & Storage
- Backup Generator
- Solar Backup Power
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// Risk Intelligence
| Threat Score | 5 / 10 Low Risk |
| Primary Hazard | Tornado / Flash Flooding |
| Secondary Hazard | Mississippi River Flooding |
| FEMA Flood Zone | Low |
| Federally Declared Disasters | 6 |
| Last Major Event | 2017 Tornado |
| Event Frequency | Annual |
// Emergency Operations
| Emergency Mgmt Phone | (618) 658-3611 |
| Emergency Shelters | 2 designated facilities |
| Evacuation Routes | State and US highways |
// County Profile
| County | Johnson County IL |
| State | Illinois (IL) |
| Population | 13 |
| Area | 346 sq miles |
| FEMA Region | Low |
// Other Illinois Counties
Cook County IL
Tornado / Severe Storm
6/10
Moderate
Will County IL
Tornado / Severe Storm
6/10
Moderate
St. Clair County IL
Tornado / Flash Flooding
6/10
Moderate
Madison County IL
Tornado / Mississippi River Flooding
6/10
Moderate
Ford County IL
Tornado / Flash Flooding
5/10
Low
Mercer County IL
Tornado / Flash Flooding
5/10
Low