Following the passage of Tropical Wave 39 on Friday, a surge of Saharan Dust is forecast to move across the Lesser Antilles, including T&T, with dust levels remaining mild through mid-September.
What you need to know
— Saharan Dust Surges: A mild to moderate Saharan Dust surge is forecast to move across T&T by Saturday, September 2nd, 2023, with mild dust levels lingering through September 9th. Higher dust concentrations are forecast to remain north of T&T.
— Impacts: Through the next seven to ten days, air quality levels across Trinidad and Tobago are forecast to remain between good and moderate.
— What Should You Do: Sensitive groups will be required to take the necessary precautions, particularly from September 2nd.
Current AQI Levels Across T&T
The official air quality monitoring stations from the Environmental Management Agency (EMA) at Point Lisas, San Fernando, and Arima are reporting good quality levels. Stations at Beetham and Signal Hill, Tobago, are not reporting PM2.5 or PM10 data as of Wednesday afternoon.
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
Saharan Dust levels are minimal through Friday, but a surge is forecast to arrive from late Friday, September 1st, 2023, following the passage of Tropical Wave 39, but higher concentrations are forecast to arrive from early Saturday, September 2nd, 2023.
Some improvement is forecast by mid-Monday, September 4th, 2023, with a mild surge of dust expected by early Wednesday, September 6th, 2023, as mild levels linger through September 9th, 2023.
Through the next seven to ten days, air quality levels across Trinidad and Tobago are forecast to remain between good and moderate. Sensitive groups will be required to take the necessary precautions, particularly from September 2nd.
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.
