Tropical cyclones i.e. Depressions, Tropical storms and Hurricanes. The Sea-Breeze effect. During these events, the prevailing easterlies are weak and onshore westerlies on the west coast may dominate, especially after a hot day to drive a front of conversion inland. The northward movement of the High and its seasonal weakening during the summer months, significantly lessen its rainfall suppressive effects on Trinidad and Tobago. The ITCZ migrates northward and affects the area.
Trade winds weaken and give way to a moister equatorial flow from the east or east-southeast.
The climatic regime changes to a more equatorial type. The other peak is found in November and can be attributed to an unstable transitional airmass before the true northeasterly trade winds reassert themselves as the ITCZ migrates again southward. November is also a month marked with upper tropospheric trough activity. Figures 2.4a and 2.4b. The Central range in Trinidad plays a similar role in enhancing the rainfall of that area.