As a result of their southerly location, Trinidad and Tobago experiences two relatively distinct seasonal climatic types: tropical maritime from January to May with warm days and cool nights with relatively low rainfall. The rainfalls at nights are mainly due to daytime convection; and modified moist equatorial climate between June and December, characterized by hot humid days and nights, low wind speeds and increased rainfall, due to convection and equatorial weather systems (Trinidad and Tobago Meteorological Services, 2009). These two climate types result in two distinct seasons, a dry season from January to May and a wet or rainy season from June to December.
- Annual mean temperature has warmed over the period 1981 – 2010 by 0.8 and 0.5°C relative to 1961 – 1990 and 1971 – 1990, respectively.
- Annual and seasonal rainfall trends for the period 1950 – 2015 are not statistically significant. However, warmer temperature is affecting the water cycle resulting on changes of the amount of rainfall during cyclone season.
- The number of tropical cyclones (including severe tropical cyclones) affecting Tonga per decade has increased (1981 – 1990, 1991 – 2000, and 2001 – 2010).