Even with the passage of Tropical Storm Fiona to the north, Saharan Dust is forecast to remain ever-present across Trinidad and Tobago over the next several days.
What you need to know
— Saharan Dust Surges: Fluctuating concentrations of Saharan Dust are forecast through the next several days, with additional surges forecast to arrive across T&T by late Saturday and next Tuesday into Wednesday.
— Impacts: Through the next seven days, air quality levels across Trinidad and Tobago will fluctuate between good and moderate levels.
— What Should You Do: Sensitive groups may need to take the necessary precautions from Sunday through Wednesday. The general population will remain unaffected.
Current AQI Levels Across T&T
The Environmental Management Agency (EMA) air quality monitoring stations at San Fernando, Point Lisas, Signal Hill, and Port of Spain have recorded good to moderate air quality levels over the last 24 hours.
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 near or above ten kilometers at the Piarco International Airport and A.N.R. Robinson International Airport at Crown Point, Tobago, outside of shower and thunderstorm activity.
Saharan Dust Forecast
Next Surge: Saturday, September 17th, 2022
As Tropical Storm Fiona moves northwestward, a surge of Saharan Dust is set to follow by late Saturday into Sunday, reducing air quality. Dust levels are forecast to remain elevated through the next several days ahead of this surge, at mild to moderate levels.
Air quality levels will vary from good to moderate across T&T, with visibility generally remaining near or above ten kilometers outside of shower or thunderstorm activity.
Surge #2: Tuesday, September 20th, 2022
Another moderate surge of dust is forecast to arrive across the Leewards and Central Lesser Antilles by late Tuesday and across the Winwards Tuesday night into Wednesday. Higher concentrations are forecast to remain north of T&T. Dust levels are forecast to diminish by Friday, September 23rd, 2022.
Air quality levels will vary from good to moderate across T&T, with visibility generally remaining near or above ten kilometers outside of shower or thunderstorm activity.
What does this mean for you?
The air quality is forecast to be degraded due to Saharan Dust over the next seven days. During high traffic periods, particularly between 6:00 AM and 9:00 AM and again from 3:00 PM through 6:30 PM, air quality may be further reduced in localized areas.
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.
