Moderate surges of Saharan Dust continue to trail tropical waves and disturbances in the Atlantic, with T&T set to experience brief periods over the next seven days of good air quality.
What you need to know
— Saharan Dust Surges: Moderate Saharan Dust surges are forecast briefly on Sunday, June 30th, and briefly again overnight from July 2nd into July 3rd, and a more prolonged moderate to high concentration surge from July 4th.
— Impacts: Air quality is forecast to generally remain good to moderate through 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 7:00 AM Friday, June 28th, 2024, the official air quality monitoring stations from the Environmental Management Agency (EMA) at Arima, Point Lisas, Toco, Beetham and San Fernando all report good air quality, while at Signal Hill, air quality is unhealthy for sensitive groups due to a surge of particulate matter overnight, likely due to a nearby fire.
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 (Friday, June 28th) through Sunday (June 30th): Mild to moderate levels of Saharan Dust, with higher levels north of T&T. Air quality good to moderate.
Sunday (June 30th) through early Monday (July 1st): Moderate levels of Saharan Dust across T&T, decreasing from early Monday morning. Air quality good to moderate.
Monday (July 1st) through mid-Tuesday (July 2nd): Little to no Saharan Dust from the mid-morning due to a low-pressure area (as of Friday, June 28th, Invest 95L/Tropical Wave 16) moving north of T&T. Good air quality.
Tuesday night (July 2nd) through Wednesday morning (July 3rd): Moderate levels of Saharan Dust across T&T, decreasing from early early morning. Air quality good to moderate.
Wednesday (July 3rd) through early Thursday (July 4th): Mild Saharan Dust as a result of the passage of Tropical Wave 17. Air quality good.
Thursday (July 4th) through Sunday (July 7th): Moderate to high concentrations of Saharan Dust across both islands, with generally moderate air quality. Another reinforcing surge of Saharan Dust is likely from late July 7th.
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 among the population. For the general public, no action is required.
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.
