Social media users have reacted to the sighting of a waterspout, a rare weather event locally known as "Isata" in Rwanda's Lake Ruhondo.

The weather occurrence relates to a spinning column of air and water suspended in the air that is formed by a whirlwind occurring over a water body.

A statement from the country's meteorological department said the powerful, funnel-shaped column of water was occurring because of differences between the temperature on the lake and the clouds hanging above.

The weatherman said this kind of cloud usually produces rain, thunder and lightning.

Some people online have been asking questions about the phenomenon.

"What kind [is] that phenomena? Happening now in RUHONDO lake," a tweeter, Natural Beauty of Rwanda, posed.

"...Someone who is better in geographical atmosphere can help," another Twitter user said.

The National Geographic Society says waterspouts are common in some waters such as the Florida Keys in the US, the islands of Greece and off the eastern coast of Australia.

It says waterspouts are similar to tornadoes but are smaller and less destructive.