So-called ‘tornado sirens’ are not always activated in response to tornadoes. Here’s everything you need to know.
DALLAS — Spring has already brought several rounds of severe storms to North Texas and severe weather season has just started.
That’s why it’s important to remain weather-aware at all times and know the steps you should take in response to severe weather. For many families, the sound of outdoor sirens is a key indicator of impending severe weather.
However, outdoor sirens, commonly, but mistakenly, known as tornado sirens, are NOT designed to alert people inside their homes to weather-related dangers. In fact, those sirens aren’t just triggered by a tornado, but by two other kinds of severe storms.
The sirens are intended to alert anyone outside that severe storms are coming and to find shelter immediately.
WFAA’s weather experts say you should not rely only on outdoor warning sirens for weather information and warnings. It’s important to have multiple ways to receive severe weather warnings including apps such as WFAA’s mobile app and streaming service WFAA+, TV and/or a weather radio.
Here’s how you can get weather alerts from WFAA sent directly to your phone, and tune into 24/7 live weather coverage when severe storms are in the area.
When and why are outdoor sirens triggered?
Individual cities decide what triggers their outdoor sirens. The conditions that prompt the sirens to sound can vary slightly by city, but most are triggered by the same things, WFAA found.
The North Central Texas Council of Governments suggests communities activate emergency sirens when the following conditions are met:
- The National Weather Service issues a Tornado Warning
- The National Weather Service Issues a Severe Thunderstorm Warning and warns of the potential for destructive winds of 70 mph or greater
- Trained storm spotters have reported a tornado in the jurisdiction, or in a neighboring jurisdiction that has the potential to affect your community
- Observed hail of 1.5” in diameter or greater
- Other emergency as directed by the community’s designated public safety officials
Some communities also activate sirens for other environmental disasters, such as hazardous materials being released into the atmosphere and emergencies that pose an immediate threat to safety such as a dam failure.
What should you do if you hear a siren? Why might you not hear a siren during severe weather events?
If you are outside when a siren sounds, you should seek shelter immediately, safety officials said. If shelter is not available, lie in a ditch, ravine culvert or other low-lying area. Cover your head and neck with your arms or a piece of clothing, the Dallas Office of Emergency Management said in a release.
If you are in a mobile home or vehicle when a siren sounds, you should abandon the mobile home or vehicle and lie flat in the nearest ditch or depression. Before a storm arrives, those living in an RV or mobile home should identify a designated shelter in their community or have a plan to evacuate to an off-site shelter location, safety officials said.
If you are inside a home or an apartment when a siren sounds, you should find shelter in a windowless, interior room.
If you don’t hear a siren during a severe weather event, it may be because the sound was drowned out by the storm or noises inside your home. That is why sirens should not solely be relied upon for weather information, officials said.
North Texas cities often have several sirens stationed around the city to achieve full coverage. In Dallas, 173 sirens are strategically placed around the city. In Fort Worth, there are 159 sirens alerting residents to severe weather.
How do I know if the sirens around me are working? When are they tested?
Sirens are typically tested monthly. Communities will delay a test if weather contentions are stormy.
Some cities, such as Fort Worth, publish an interactive map showing which sirens may not be working. If you’re concerned a siren in your neighborhood is not working, you should contact your city’s Office of Emergency Management.
