TTMS: Very Fine Ash From La Soufrière Can Be Present In 36-48 Hours In T&T

Volcanic Ash Advisory for La Soufrière from the Washington DC Volcanic Ash Advisory Center for the next 36 hours

Present La Soufrière Alert Level:ORANGEThere is a highly elevated level of seismic and/or fumarolic activity or other unusual activity. An eruption may begin with less than twenty-four hours’ notice.

The Trinidad and Tobago Meteorological Service (TTMS) says there is a low (20%) probability of ash particles from the La Soufrière Volcano in St Vincent reaching Trinidad and Tobago over the next 36-48 hours.

In their official statement issued at 12:30 PM Tuesday 13th April 2021, they say, “The wind regime is, however, changing, and the plume is migrating to the east of our islands, but in the upper layers of the atmosphere.”

At that level, only very fine ash particles are present, mainly causing an aviation hazard. The TTMS also states, “This ash may not be highly discernable as there is still a moderate concentration of Saharan dust in our atmosphere. Despite this, the TTMS maintains that all precautionary measures should be taken by the relevant stakeholders and persons with health concerns.”

Volcanic Ash Advisory (Observed Ash for La Soufrière from the Washington DC Volcanic Ash Advisory Center issued at 2:30 PM April 13th, 2021
Volcanic Ash Advisory (Observed Ash) for La Soufrière from the Washington DC Volcanic Ash Advisory Center issued at 12:45 PM April 13th, 2021

Based on the Washington DC Volcanic Ash Advisory Center’s latest observations, there are three separate ash clouds they are monitoring as of 12:30 PM local time. The first, up to 24,000 feet in the atmosphere, is moving to the northeast at 15 knots, predominantly affecting St. Lucia.

The second is a widely dispersed ash cloud from yesterday’s eruptions, lofting just north of South America, between Guyana and French Guiana, up to 40,000 feet. It moves to the southeast at 30 knots and is forecast to disperse over the next 6 hours.

Volcanic Ash Advisory (Forecast for 6:30 PM April 13th, 2021) for La Soufrière from the Washington DC Volcanic Ash Advisory Center issued at 12:45 PM April 13th, 2021
Volcanic Ash Advisory (Forecast for 6:30 PM April 13th, 2021) for La Soufrière from the Washington DC Volcanic Ash Advisory Center issued at 12:45 PM April 13th, 2021

The third ash cloud was emitted by La Soufrière from this morning’s 6:30 AM eruption, where ash is drifting across and southeast of Barbados at this time. This ash cloud is forecast to continue moving to the southeast at 25 knots, between the surface and up to 35,000 feet in the atmosphere.

Volcanic Ash Advisory (Forecast for 12:30 AM April 14th, 2021) for La Soufrière from the Washington DC Volcanic Ash Advisory Center issued at 12:45 PM April 13th, 2021
Volcanic Ash Advisory (Forecast for 12:30 AM April 14th, 2021) for La Soufrière from the Washington DC Volcanic Ash Advisory Center issued at 12:45 PM April 13th, 2021

Note that traceable ash clouds continue to remain east of Trinidad and Tobago on its journey southeast, but possibly affect parts of northern coastal South America, including Guyana, Suriname and French Guiana.

Volcanic Ash Advisory (Forecast for 6:30 AM April 14th, 2021) for La Soufrière from the Washington DC Volcanic Ash Advisory Center issued at 12:45 PM April 13th, 2021
Volcanic Ash Advisory (Forecast for 6:30 AM April 14th, 2021) for La Soufrière from the Washington DC Volcanic Ash Advisory Center issued at 12:45 PM April 13th, 2021

It is also important to note as ash travels these large distances, only very fine ash particles will be present, mainly being an aviation hazard and somewhat reducing visibility. Sky conditions may look no different than a very hazy day due to Saharan Dust, as moderate to high concentrations remain present across the region.

Widespread ashfall and impacts similar to Barbados and St. Vincent are NOT expected in Trinidad and Tobago.

On the ground, if you capture rainwater, you would notice the water being dark, at times black. On vehicles or other surfaces outdoors, you would notice spots of dust or sand as rainfall dries. Again, this is typical during moderate to significant Saharan Dust events.

Rainfall collected in a bucket in Maraval, Trinidad following afternoon showers on Sunday 11th April 2021 (Emma Marcano)
Rainfall collected in a bucket in Maraval, Trinidad following afternoon showers on Sunday 11th April 2021 (Emma Marcano)

What should you do? Follow air quality guidelines, as Saharan Dust through the next several days will be the main contributor to air quality pollution. For those that experience “dirty rainfall,” it is recommended to wash your vehicle off with water initially to remove particles and avoid the abrasive impacts on your property. Ashfall in Trinidad and Tobago will not significantly affect air quality based on the latest air quality models.

Ash clouds are still forecast to continue moving to the east and southeast, away from Trinidad and Tobago so any measurable amount of ashfall is unlikely.

Volcanic Hazard Map for the La Soufrière Volcano, St. Vincent (UWI SRC/NEMO)
Volcanic Hazard Map for the La Soufrière Volcano, St. Vincent (UWI SRC/NEMO)

Official information will originate from St. Vincent and the Grenadines National Emergency Management Organization and the University of the West Indies Seismic Research Center.

Facebook Comments