Ever since the North Dallas tornado tore through neighborhoods in 2019, the sound of outdoor warning sirens has taken on a new intensity for many of us. That sudden wail can jolt even the calmest among us. But what do the sirens actually mean — and how should you respond?
Cities and counties across North Texas, including Dallas, Fort Worth, Frisco, Plano, and Arlington, operate outdoor warning sirens as part of their emergency alert systems. These sirens are not just for tornadoes — they’re designed to alert people outside that dangerous conditions are imminent. If you hear them, it’s not the time to speculate — it’s time to act.
When Do the Sirens Sound?
In most North Texas cities, including Dallas and Fort Worth, outdoor warning sirens are activated when any of the following occur:
- A tornado warning is issued by the National Weather Service within city limits or nearby.
- Winds exceed 70 mph, which can cause widespread damage.
- Hail of 1.5 inches or larger is detected.
- A confirmed tornado or funnel cloud is reported by trained storm spotters.
- Other emergency situations, such as a hazardous materials spill, where immediate mass notification is necessary.
Frisco will activate its sirens under slightly different criteria: hail of 1.25 inches or greater, winds of 70 mph or more, or any tornado threat.
Plano uses similar guidelines, sounding sirens for:
- Tornado warnings within city limits.
- Winds greater than 70 mph.
- Hail larger than 1.25 inches.
- Confirmed tornado sightings.
Arlington’s sirens are activated during:
- Tornado warnings or sightings.
- Extreme wind events (generally 70+ mph).
- Hail greater than 1.25 inches in diameter.
It’s worth repeating: these are not “tornado sirens.” The term is outdated. They’re outdoor warning sirens that indicate any type of immediate threat, not just tornadic activity. They don’t tell you what the danger is — only that it’s time to seek shelter.
What Should You Do When You Hear the Sirens?
- Get inside immediately. Go to an interior room on the lowest floor, away from windows.
- Grab your pre-packed emergency bag with a weather radio, flashlight with extra batteries, a wrench or pliers to turn off utilities, bottled water and shelf stable food, a first-aid kit, and other items on an emergency preparedness checklist.
- Use a weather app, NOAA weather radio, or local news to get more information. The sirens don’t give details, so you’ll need a secondary source.
- Stay alert. Even if your area seems calm, severe weather can move quickly and conditions can change in minutes.
The outdoor warning system is tested on the first Wednesday of every month at noon if there’s no threatening weather. This helps ensure that there is no confusion about if it’s a test or a real activation.
Watch vs. Warning: What’s the Difference?
It’s easy to confuse the two — here’s the quick breakdown:
- Watch: Conditions are favorable for dangerous weather. Keep an eye on the sky and stay close to shelter.
- Warning: Severe weather is happening or imminent. Take cover immediately.
Hail
Curious about the various hail sizes? Here’s the guide according to the City of McKinney Emergency Preparedness office:…