Over the next seven days, Saharan Dust surges are forecast to trail tropical waves, with the first, short-lived surge forecast to move across T&T from early Thursday, trailing Tropical Wave 18. Generally, through the end of the month, higher dust levels are forecast to remain north of T&T.
What you need to know
— Saharan Dust Surges: Through Wednesday morning, a mild dust surge is moving across T&T. A moderate surge of Saharan Dust will move across T&T from early Thursday (July 24th) with higher concentrations of dust across the northern half of the island chain. Concentrations are expected to decrease by Saturday morning (26th), and another short-lived but mild surge is forecast between Sunday morning (27th) and Monday night (28th). Dust-free days are forecast to be interrupted by another mild to moderate dust surge by Thursday (July 31st).
— What Should You Do: Unusually sensitive groups are advised to take necessary precautions, particularly between Thursday and Sunday, while the general public remains mostly unaffected over the next seven to 10 days.
Current AQI Levels Across T&T
As of 3:00 AM Wednesday, July 23rd, 2025, the official air quality monitoring stations from the Environmental Management Agency (EMA) at Beetham outside of Port of Spain, San Fernando, Mayaro, King’s Bay (Tobago), Mayaro and Point Lisas report air quality that are at good to slightly moderate levels based on PM2.5 or PM10 data.
Unofficial air quality monitoring stations at Longdenville and Woodbrook report air quality levels that are good.
These measurements are based on PM2.5 (particulates smaller than 2.5 micrometers in size, typically associated with increases in Saharan Dust, vehicle exhaust, and smoke) and PM10 particulates.
Outside of rainfall, visibility, used as a proxy for Saharan Dust concentrations, at the A.N.R. Robinson International Airport at Crown Point, Tobago, and Piarco, remains at 10 kilometers over the last 24 hours.
Saharan Dust Forecast For T&T
July 23rd: Mild concentrations of Saharan Dust with air quality levels generally at good levels, improving from moderate. Horizontal visibility is generally unaffected by dust.
July 24th through July 25th: Moderate concentrations of Saharan Dust, with peak concentrations likely on Thursday (10th), with air quality generally near moderate levels. Horizontal visibility is likely to dip between 8 and 10 kilometers on days with peak concentrations.
July 26th: Mild concentrations of Saharan Dust with air quality generally at good levels, occasionally at moderate levels. Horizontal visibility is likely to remain at or above 10 kilometers.
July 27th to July 28th: Mild (Trinidad) to moderate (Tobago) concentrations of Saharan Dust with air quality at good to moderate levels. Horizontal visibility generally at 10 kilometers.
July 29th through early July 31st: Little to no Saharan Dust forecast with air quality at good levels. Horizontal visibility is generally unaffected by dust.
What does this mean for you?
Generally, over the next 10 days, air quality levels are forecast to be mainly moderate, with periods of good air quality during the passage of the ITCZ or tropical waves.
We’re now 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.
Peak dust concentrations climatologically occur during June across the Main Development Region of the Atlantic, just east of Trinidad and Tobago.
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, they kick up dust as they move across parts of the Saharan Desert and transport it into the upper atmosphere. This “plume” of dust follows the axis of the wave as it progresses westward into the Atlantic.
Dust that enters the upper levels of the atmosphere can then be 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.
