February 2021 is forecast to be off to a dusty start with two surges of Saharan Dust forecast to move across T&T over the next 5 days. Concentrations of Saharan Dust are forecast to fluctuate through the weekend and next week while higher concentrations remain to our east.
This surge of dust will coincide with a surge in trade winds and swells, causing breezy conditions across T&T, agitating seas in open waters, and causing hazardous conditions in nearshore areas like bays and beaches.
The Environmental Management Agency (EMA) air quality monitoring stations are recording AQI values at levels that are good to moderate in Trinidad and Tobago 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
Saharan Dust concentrations are forecast to gradually increase over the next 72 hours, with moderate to high concentrations after midnight Saturday into Sunday.
Peak concentrations are forecast on Sunday 31st January 2021, with concentrations fluctuating through next week as another surge arrives on Tuesday.
Based on the latest dust modeling, air quality across Trinidad and Tobago will vary between good to moderate levels, possibly reaching levels that are unhealthy for sensitive groups in areas where high traffic or fires occur, particularly on Sunday 31st January 2021.
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 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.