Elevated concentrations of Saharan Dust are forecast to continue affecting Trinidad and Tobago over the next ten days, with higher dust levels remaining north of the country. Periodic surges in dust are forecast to trail tropical waves in the Atlantic, typical for this time of year.
What you need to know
— Saharan Dust Surges: Concentrations are set to decrease across T&T (but increase across the Leewards) by Friday as back-to-back tropical waves move across the region, with the next dust surge arriving by early Saturday, July 13th, with concentrations forecast to be moderate to high. Improvement is forecast once more between Monday and Wednesday next week before another moderate to high-concentration surge moves in.
— Impacts: Air quality is forecast to remain good to moderate throughout the forecast period.
— 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
As of 3:00 PM Wednesday, July 10th, 2024, the official air quality monitoring stations from the Environmental Management Agency (EMA) at Arima, Point Lisas, Toco, and San Fernando all report moderate air quality, while at Signal Hill, Mayaro, and Beetham, no data is currently being transmitted.
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 For T&T
Now through Friday (July 12th): Decreasing Saharan Dust levels due to the passage of Tropical Waves 19 and 20 north of T&T, with an increase in dust levels trailing. Mostly good to moderate air quality.
Saturday (July 13th) through Sunday (July 14th): Moderate to high concentrations of Saharan Dust across both islands, with generally moderate air quality.
Monday (July 15th) through mid-Wednesday (July 17th): Mild to moderate Saharan Dust levels across both islands, with generally good air quality, particularly Tuesday into early Wednesday.
Mid-Wednesday (July 17th) through Saturday (July 20th): Moderate to high concentrations of Saharan Dust with air quality between good and moderate levels.
What does this mean for you?
Elevated concentrations of Saharan Dust periodically over the next seven to ten days are likely to bring air quality to moderate levels, chiefly affecting the most sensitive groups of the population. The general public is not required to take action.
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.
