Saharan Dust is set to return later on Sunday as a brief plume of dust makes its way across the Southern Windwards, including Trinidad and Tobago. Reduced air quality and hazy skies may linger until midweek, where dust concentrations are forecast to subside.
The Environmental Management Agency (EMA) air quality monitoring stations are recording AQI values at levels that are good in Trinidad and Tobago as of Saturday night. These measurements are based on PM2.5 (particulates the size of 2.5 micrometers and smaller, usually associated with increases in Saharan Dust, vehicle exhaust, and smoke) and PM10 particulates.
The Saharan Dust Forecast
This surge of Saharan Dust is forecast to move across T&T on Sunday 14th February 2021 through Tuesday 16th February 2021. By mid-week, Saharan Dust concentrations will gradually diminish, with very mild concentrations present as the dust won’t entirely go away.
The next surge of dust is forecast to be mild, arriving across T&T by February 20th, 2021. This will not be a significant surge.
Based on the latest dust modeling, air quality across Trinidad and Tobago will vary between good to moderate levels, particularly in areas where high traffic or fires occur.
What does this mean for you?
For the general population, with mild Saharan dust concentrations possible, little to no impacts are forecast beyond slightly hazy skies. 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 a ridge of high pressure stays over the central Sahara Desert, and the Intertropical Convergence Zone (ITCZ) remains over the Gulf of Guinea.
The Harmattan wind accelerates when it blows across the mountain massifs of Northwest Africa. If its speed is high enough and it blows over dust source regions, it lifts the dust and disperses it.
Dust that makes it into the upper levels of the atmosphere can then get transported across the Atlantic Ocean and affect the Eastern Caribbean.
These Saharan Dust outbreaks tend to be milder in the Eastern Caribbean than the dust outbreaks associated with West African thunderstorms driving dust into the upper atmosphere from April through November.