An Adverse Weather Alert yellow level will take effect from 5am Thursday to 5pm Friday.
It was issued at 2:48pm Wednesday.
The Met Service says showers and rainfall of varying intensities associated with an active Tropical Wave, are expected to begin affecting Tobago from near midnight into early morning and then spreading to Trinidad from early morning throughout the day.
There is a medium to high chance of accompanying thunderstorm activity and gusty winds in excess of 55km/h, likely especially in areas near heavier showers or well developed thunderstorms.
Isolated flash floods, street flooding and localized ponding can cause temporary traffic disruptions.
Landslips are possible in areas so prone.
Gusty winds can lead to broken tree branches and loose/unsecured items being displaced.
Seas can become agitated due to strong winds. Marine operations can be temporarily disrupted.
The public is asked to restrict outdoor activity and do not venture into flood waters.
Secure loose items and take the necessary precautions in sea related activities.
Monitor weather conditions and updates from official sources via www.metoffice.gov.tt and www.odpm.gov.tt.