Moderate concentrations of Saharan Dust remain across Trinidad and Tobago into the weekend, while higher dust levels are moving across the Caribbean Sea and the Greater Antilles, heading toward the southeastern United States.
What you need to know
— Saharan Dust Surges: Moderate concentrations of Saharan Dust will decrease by late Sunday, July 23rd, 2023, with a brief surge by late Monday, July 24th through early July 25th. Mild dust levels will remain across T&T through Thursday, July 27th, 2023. Another brief, mild to moderate dust surge is forecast from Friday, July 28th, 2023.
— Impacts: Through the next seven to ten days, air quality levels across Trinidad and Tobago are forecast to remain between good and moderate levels. Islands north of Trinidad and Tobago could see further reductions in air quality and visibility. Air quality levels may reduce to unhealthy for sensitive groups in T&T on July 22nd.
— What Should You Do: Sensitive groups may need to take the necessary precautions, 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 Point Lisas, Arima, and San Fernando are reporting moderate quality levels. Stations at Beetham, and Signal Hill, Tobago, are not reporting PM2.5 or PM10 data as of Monday 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
High-Concentration Saharan Dust Surge Moving Across Greater Antilles
Moderate dust levels are moving across the southern Windwards, with higher concentrations now moving across the Leewards, Greater Antilles, and the Caribbean Sea on Friday afternoon. Dust concentrations are forecast to diminish across T&T through the weekend, returning to mild levels by Monday, July 24th, 2023.
A brief and mild to moderate surge of dust is forecast to move across the region late Monday, July 24th, 2023, into late Tuesday, July 25th, 2023, with higher dust concentrations north of Trinidad and Tobago.
Little to no dust is forecast across the country from mid-Wednesday, July 26th, 2023, through Friday, July 28th, 2023, when a moderate surge of dust arrives into the final weekend of July.
However, improvement is forecast by Sunday, July 30th, 2023, with little to no dust across T&T to close out the month.
Through the next seven to ten days, air quality levels across Trinidad and Tobago are forecast to remain between good and moderate levels. Islands north of Trinidad and Tobago could see further reductions in air quality and visibility. Air quality levels may reduce to unhealthy for sensitive groups in T&T through July 22nd.
What does this mean for you?
The air quality is forecast to be lowered primarily during high traffic periods, particularly between 6:00 AM and 9:00 AM and again from 3:00 PM through 6:30 PM.
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.
