Saharan dust concentrations, as forecast, have increased across the Southern Windwards on Wednesday, including Trinidad and Tobago. Air quality is now at moderate levels across Trinidad, Tobago, Grenada, Barbados, St. Vincent and the Grenadines and St. Lucia.
The surge of Saharan dust is forecast to intensify through the weekend, with higher concentrations remaining north of T&T. Concentrations are forecast to diminish by Wednesday 25th November 2020.
Across the country, air quality is at moderate levels presently with visibility above 10 kilometers as of 12:00 PM Wednesday 18th November 2020.
The Saharan Dust Forecast
Based on the latest dust modeling, air quality across Trinidad and Tobago is forecast to remain at moderate levels through next Wednesday (18th November 2020). Concentrations are forecast to peak on Sunday into Monday.
The good news is that due to the passage of Tropical Wave 66 on Friday into Saturday, much of the higher concentrations are forecast to remain north of T&T.
Improvement is forecast from Wednesday 25th November 2020, with another surge of dust forecast to return by the beginning of December.
What does this mean for you?
For the general population, with mild to moderate Saharan dust concentrations forecast, little to no impacts are forecast beyond reduced visibility. For sensitive groups, such as children, the elderly, and persons who suffer from respiratory ailments and allergies, you may need to avoid prolonged exertion outdoors.
We’re in a period where the ITCZ, tropical waves, and occasional tropical cyclones shield Trinidad and Tobago from the Saharan Dust events. While tropical waves play a notable role in moving dust across the Atlantic and the Eastern Caribbean, these frequent tropical waves also improve air quality.
The concentration of the dust that follows the wave depends on the strength of the wave as it moves off the West African Coast. This is because of stronger thunderstorms across Central Africa. As strong winds move downward and outward from these thunderstorms, the wind kicks up dust as it moves across parts of the Saharan Desert and transports it into the upper atmosphere. This “plume” of dust follows the axis of the wave as it progresses westward into the Atlantic.
Larger, more concentrated plumes of Saharan dust begin to occur in April and continue through November.