An updated bulletin issued by the Met Office now forecasts that Tropical Storm conditions can be felt as early as 9 pm.
The Met Office had previously indicated in its 6 am forecast that the Tropical Storm effects could be felt in some 18 hours, that is, at midnight.
However, in a subsequent bulletin issued at 9 am, the Met Office revised that time to "within 12-18 hours", or, around 9pm.
The following is the Met Office's latest bulletin.
"Tropical Storm Warning remains in effect for Trinidad and Tobago, Grenada and its Dependencies.
A Tropical Storm Warning means that Trinidad and Tobago, Grenada and its Dependencies can expect Tropical Storm conditions within 12 –18 hours.
At 8:00am, Monday June 19, 2017, the centre of Potential Tropical Cyclone #2 was located near 8.7ºN latitude 55.7ºW longitude or about 645 kilometres east-southeast of Trinidad.
A Potential Tropical Cyclone refers to a disturbance that has not yet become a tropical cyclone, but which poses the threat of bringing tropical storm or hurricane conditions to land areas within 48 hours.
Potential Tropical Cyclone #2 is moving to the west at about 37 km/hr.
The disturbance is expected to continue on west-northwest track over the next 48 hours during which it is forecast to intensify as environmental conditions are conducive for strengthening.
Maximum sustained winds are near 65km/hr with higher gusts.
Minimum central pressure is 1005mb. Trinidad and Tobago, Grenada and its Dependencies will therefore be mostly exposed to Tropical Storm conditions from Monday evening into Tuesday.
The disturbance is expected to produce total rainfall accumulations of 50 to 125mm over Trinidad and Tobago, Grenada and its Dependencies from Monday afternoon through Tuesday.
Gusty winds and street/flash flooding are likely in areas of heavy showers or thundershowers. The possibility of landslides/landslips exists. Sea conditions are also anticipated to become very disturbed which will adversely affect marine and coastline interests.
Citizens and all concerned are advised to closely follow the directions and advise of their Disaster Emergency Managers at this time.
Adopt all necessary measures to preserve life and property. The disturbance 8:00am position: 8.7ºN latitude 55.7ºW longitude or about 645 kilometres east-southeast of Trinidad. The Trinidad and Tobago Meteorological Service will issue another bulletin at 12:00pm, Monday 19th June, 2017.
All interests in Trinidad and Tobago are asked to monitor the progress of this system and pay close attention to information being issued by the TTMS by visiting our website at www.metoffice.gov.tt, downloading our mobile app (search: TT Met Office) and following us on Twitter and Facebook."