Keening

The keening whistle of the teapot signaled that the water was boiling.

The keening sound of the ambulance siren signaled a tragedy unfolding on the streets.

The distant keening of the siren warned of an approaching storm.

The piercing sound of keening could be heard from miles away, signaling the loss of a respected community leader.

The keening sound of the ambulance siren pierced through the busy city streets.