Following a fairly wet couple of days, Trinidad and Tobago is forecast to experience elevated levels of Saharan Dust amid brief periods of improvement as tropical waves traverse the region.
What you need to know
— Saharan Dust Surges: A moderate to high concentration Saharan Dust surge is moving into the area currently, with another surge by Tuesday, June 18th, 2024.
— Impacts: Air quality is forecast to range from good to moderate, occasionally reaching levels that are unhealthy for sensitive groups in the vicinity of smoke, fires, or high traffic.
— What Should You Do: In times of unhealthy air quality, everyone should take the necessary precautions. Throughout the forecast period, sensitive groups are advised to take the necessary precautions, particularly during high traffic and in the vicinity of fires.
Current AQI Levels Across T&T
The official air quality monitoring stations from the Environmental Management Agency (EMA) at Arima, Point Lisas, Toco, San Fernando, and Mayaro are all reporting good levels, while at Beetham, moderate air quality is observed. There is no data from Scarborough.
Unofficial air quality monitoring stations at Longdenville, St. Augustine, and Woodbrook are reporting good air quality.
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 has remained at 10 kilometers at the A.N.R. Robinson International Airport at Crown Point, Tobago, and at the Piarco International Airport, Trinidad, outside of rainfall activity.
Saharan Dust Forecast
Now through Sunday (June 16th): Increasing dust levels by nightfall on Tuesday. Moderate to high concentrations of Saharan Dust throughout the period, with air quality generally at moderate levels.
Mid-Sunday (June 16th) through early Tuesday (June 18th): Mild Saharan Dust across Trinidad and Tobago, with higher dust levels north of the southern Windward Islands. Air quality good to moderate levels.
Early Tuesday (June 18th) through Saturday (June 22nd): Fluctuating moderate dust levels present across both islands, with air quality at good to moderate levels.
What does this mean for you?
With elevated concentrations present and drier and breezier conditions bringing the risk of fires, air quality is still forecast to be reduced, with further reductions in localized areas of fires, blowing smoke and dust, and high traffic.
We’re in a period where the Intertropical Convergence Zone, tropical waves, and occasional tropical cyclones may shield Trinidad and Tobago from the Saharan Dust events. While tropical waves are notable 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.
