After several dust-free days, Saharan Dust is forecast to increase across Trinidad and Tobago from Friday afternoon, with peak concentrations forecast later this upcoming weekend.
What you need to know
— Saharan Dust Surges: The next surge of Saharan Dust is forecast to move across T&T and the Eastern Caribbean by late Thursday into Friday, October 6th, 2023, following the passage of Tropical Wave 49, with mild to moderate concentrations lingering into the next week.
— Impacts: Through the next seven to ten days, air quality levels across Trinidad and Tobago are forecast to remain near good, reaching near moderate between late October 6th through October 10th, 2023.
— What Should You Do: Sensitive groups are advised to take the necessary precautions from October 6th, particularly during high traffic periods and in the vicinity of bushfires.
Current AQI Levels Across T&T
The official air quality monitoring stations from the Environmental Management Agency (EMA) at San Fernando and Arima are reporting moderate air quality levels, while at Point Lisas, air quality is good. Stations at Beetham, and Signal Hill, Tobago, are not reporting PM2.5 or PM10 data as of Wednesday 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.
Over the last 24 hours, visibility remained unaffected by Saharan Dust and smoke at the A.N.R. Robinson International Airport at Crown Point, Tobago, and at the Piarco International Airport, Trinidad.
Saharan Dust Forecast
Now through early October 6th, no Saharan Dust is forecast across Trinidad and Tobago as Tropical Wave 49 nears the region.
From late Friday, October 6th, 2023, Saharan Dust levels are forecast to gradually increase, with peak concentrations on Sunday, October 8th, through Monday, October 9th, 2023. Overall higher dust levels are forecast to remain north of Trinidad and Tobago.
Through the next seven to ten days, air quality levels across Trinidad and Tobago are forecast to remain near good, reaching near moderate following October 6th, 2023. Air quality may be further reduced in the vicinity of bush or landfill fires.
What does this mean for you?
We’re in a period where the Intertropical Convergence Zone and tropical waves and occasional tropical cyclones may 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 periodic tropical waves also improve air quality.
The concentration of the dust that follows the wave depends on its strength 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.
Dust that makes it into the upper levels of the atmosphere can then get transported across the Atlantic Ocean. The plumes of dust eventually affect the Eastern Caribbean.
Larger, more concentrated plumes of Saharan dust begin in April and continue through November.
