Take Precautions Against Lightning Strikes – MET Service

Jamaicans are being advised to take extra precautions when it comes to lightning, as it can result in the loss of lives as well as destroy properties and livelihoods.

Speaking with JIS News, Head of the Weather Branch at the Meteorological Service of Jamaica (Met Service), Rohan Brown, says that of all the meteorological hazards, lightening “is the least appreciated”, but can be very dangerous.

As such, he says that the Met Service, along with other key partners, including the Office of Disaster Preparedness and Emergency Management (ODPEM), is trying to increase public awareness about this hazard.

Explaining how lightning forms, Mr. Brown says, “This occurs during the day when you have unstable weather conditions and the cloud begins to grow vertically. As they grow, they reach such a high extent that they cross what is called the freezing line.”

When this crossing of the freezing line takes place, ice crystals are formed.

Mr. Brown further illustrates that while the ice crystals are pulled downward by gravity, they also go upward because of the updraft in the clouds.

This upward and downward movement, along with the transfer of electrons, causes a separation of charge.

“So, at the top of those large, dark, ominous cumulonimbus clouds, you have positively charged particles and at the bottom you have negatively charged particles and that also induces a charge at the ground. In this, the ground has a positive charge and with that separation of charge, electricity is discharged, resulting in a flash of light called lightning,” he explains.

Mr. Brown shares, further: “You could have lightning between a cloud as an intra lightning [and] you could have lightning between two different clouds. [It can also occur] between the cloud and the ground as well as what we call ‘blue sky’ or ‘blue lightning’ where you do not see the cloud, but because of the high vertical extent, you have a charged difference and you have lightning.”

Given the basis on which lightnings form and the various ways in which they can occur, Mr. Brown is encouraging persons to be aware of the signs that can lead to a lightning strike and take the necessary steps to safeguard themselves.

He says that dark, ominous clouds are normally associated with lightning, so whenever one appears, there is a high possibility of lightning.

On the other hand, persons might be seeing clear skies and suddenly hear the thunder roar, which is a sign that lightning is about to occur.

The Head of the Weather Branch notes, further: “Once you are hearing thunder, chances are you could be in the path of lightning because even though you are not seeing that dark cloud, it means that there is a separation of charge that would have caused that lightning, and that charge could affect you as well.”

Mr. Brown says that while in Jamaica lightning occurs most frequently during the summer months, “systems like cold fronts that occur anywhere between November and April can also cause the generation of lightning”.

Additionally, he says, “depending on the type of year, you might have an increase in lightning strikes as you move from the east of the island towards the west”.

“Also, if you have a tropical wave that’s coming from the east and you have cumulonimbus clouds growing… as the clouds move toward the west of the island, the heating from the ground will allow for more convective activity,” he points out.

It is for this reason, Mr. Brown says, that the meteorological community worldwide is increasing its efforts to bring across more public awareness so that people can “appreciate” this hazard.

“It doesn’t matter where you are; lightning can affect you… . It affects almost everybody and our message is, if you hear the thunder roar, get indoors because lightning is possible and it can affect you,” he says.

Persons are advised to get into an enclosed building immediately at the sound of thunder, or a hardtop vehicle with windows and doors closed.

All outdoor games and activities should be suspended during a thunderstorm and persons instructed to get indoors.

If there is no shelter, persons are advised to crouch down in the open with arms covering their head.

Because lightning hits the tallest object, persons are advised to stay away from trees, avoid leaning against vehicles, and get off bicycles and motorcycles.

Water is a great conductor of electricity, so persons should get out of the swimming pool, ocean, and small boats or canoes.

If caught in a boat, crouch down in the centre of the boat away from metal hardware.

Do not stand in puddles of water, even if wearing rubber boots.

Persons should stay away from metallic objects such as clotheslines and fences, avoid using faucets, and drop items that have metallic fastenings such as backpacks.

Large metal objects can conduct lightning, and small metal objects can cause burns.

Also, avoid using electronic equipment, including cellular phones.