The plant's warning siren had alerted everyone at the experimental station.
Air pumped in as the warning sirens died away.
The warning sirens gave many time to act to save themselves.
But the speech was less a call to war than a warning siren.
All morning, the phrase "wind chill" had been a warning siren on the radio.
He was standing by the central fountain when the city's warning sirens sounded.
The warning siren sounded and I lay back on my couch.
The answer came in the form of shrill warning sirens from the climate control.
The hall was filled with the shriek of a warning siren.
The warning sirens had been silenced, and there was no anxiety in the faces he passed.