A tropical wave on 18 October at 0600UTC in the eastern Caribbean Sea with significant moisture in the lower and middle levels led to the development of heavy showers and thunderstorms in the Lesser Antilles.

Trinidad was affected by heavy precipitation between 18 October at 0930UTC and 20 October at 1530UTC. The Rainfall Index Loss calculated for this Covered Area Rainfall Event (CARE) that started on 18 October and ended on 20 October 2017