ILOILO – Hailstones in a tropical country like the Philippines?
It’s possible if certain conditions are met, according to the Provincial Disaster Risk Reduction and Management Office (PDRRMO).
Hailstones are small lumps of ice that form in the clouds and fall to the ground. Their size reaches 5 mm in diameter, or larger.
Hailstones rained on Barangay Lanag, Santa Barbara town around 4 p.m. on June 4 and on Barangay Botong, Badiangan on May 22. Villagers were baffled. It was a new experience for them.
Hailstones begin as water droplets that freeze in certain kinds of clouds called culumonimbus. These are thunder clouds.
“Ang clouds tama ka tugnaw kag naga-porma sang ice,” said Jerry Bionat, PDRRMO chief.
If the cloud is large enough and the winds are strong enough, hailstones can be formed.
Cloud contains tiny droplets of water. Under the right conditions, these droplets are blow to the top of the cloud by strong winds, called up-drafts.
The temperatures at the top of the cloud are a lot lower than at the bottom so the water droplets freeze rapidly. Then they can be caught by winds, called down-drafts that carry the frozen droplet back down to the lower part of the cloud.
It gets lifted again, by another up-draft and combines with another droplet of water, which freezes, forming a larger lump of ice.
Every time it travels up to the top of the cloud it merges with more droplets and gets larger, freezing in layers, until eventually it is too big and heavy to stay in the cloud and it falls to the ground as hail.
Hailstones usually fall once they are 5 mm in diameter or larger./PN
