- A tornado is in the immediate vicinity.
- Severe weather conditions with winds exceeding 70 mph.
- The presence of 1.5 inches or larger hail.
- An elected official or the University President has ordered the activation of the siren for other emergencies.
- Testing is conducted on the first Wednesday of each month at 12:30 p.m., provided the weather is clear.
Additionally, the City of Arlington also conducts tests of their OWS on the first Wednesday of every month at 1 p.m.