Tornadoes are nature’s most violent storms. They can appear without warning and might not be seen until debris is picked up or a funnel cloud appears. Tornado winds can reach 300 mph. Tornadoes cause damage when they touch down on the ground. They can damage an area as large as one mile wide and 50 miles long. It is important to plan and practice how you will take shelter during a tornado. You must be ready to act fast. From the years of 1950 to 2015, Philadelphia had eight tornadoes hit the city.
More frequently, Philadelphia will experience winds that are strong enough to cause light damage to trees, buildings and may or may not bring along rain, snow, sleet or hail. These types of winds are known as windstorms. Wind speeds during a windstorm go beyond 34 miles per hour (mph). From the years of 1950 to 2015, Philadelphia had 2,074 wind-related events, where the wind speeds were over 34 mph.
Differences between a warning and a watch
Tornado watch
Issued to alert people to the possibility of a tornado developing in the area. At this point, a tornado has not been seen but the conditions are very favorable for a tornado to occur at any moment.
What to watch for during a tornado watch:
- Dark greenish or orange-gray skies
- Large hail
- Large, dark, low-lying, rotating or funnel-shaped clouds
- A loud roar that is similar to a freight train
Tornado warning
Issued to alert people when a tornado has actually been sighted or has been picked up on radar in the area. Take shelter immediately in a safe sturdy structure.
Before a tornado or windstorm
Determine where you will take shelter in the event of a tornado warning or windstorm. The basement or the lowest part of your home is the safest. If you do not have an underground area, use an inside room or hallway without any windows.
Prepare for tornado season with a mobile app
The American Red Cross Tornado App can help you prepare for a tornado. The app offers step-by-step advice on how to get ready for a tornado. The app also provides a list of nearby shelters and an audible siren that goes off when the National Oceanic and Atmospheric Administration (NOAA) releases a warning. The app is available for Android or Apple devices.
During a tornado
- Stay tuned to local radio and TV stations or (NOAA) Weather Radio during a tornado watch. Stay updated on the weather and be ready to take shelter quickly, if necessary.
- Stay away from windows, doors, and outside walls. Go to the center of the room. Stay away from corners, which attract debris.
- Lie flat in a ditch or other low-lying area if you cannot find shelter. Do not take cover under an overpass or bridge.
- Grab your go bag and leave immediately if it is safe and you are told to evacuate.
- Do not touch or go near downed power lines.