Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Idaho to Port of Spain as you normally would.
In terms of precipitation, rainfall in Port of Spain ranges from 1.2 - 9.8 inches per month. June is typically the wettest month, when rainfall can reach 9.8 in. March is typically the driest time to visit Port of Spain when rainfall is around 1.2 in.
If weather is an important factor for your trip to Port of Spain, use this chart to help with planning. For those seeking warmer temperatures, April is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 77.0 F).