Funnel clouds, twisters, tornados: What are they?
During the stormy weather over the weekend and on Monday, BBC Scotland news website readers have been sending pictures of funnel clouds. But what are they and why are we getting them?
A funnel cloud usually forms during a thunderstorm or heavy shower, from a cumulonimbus cloud or a large cumulus cloud, when the atmosphere is unstable.
It consists of condensed water droplets and is associated with a column of air that rotates as it is drawn into the cloud.
Funnel clouds look like cone-shaped or thin rope-like protuberances which hang down from the cloud base, and often do not last very long.
If a funnel cloud touches the ground it is generally regarded as a tornado and could lift debris and even cause some minor damage on the ground - depending on the strength of convection within the cloud.
If the funnel cloud touches down at sea we get what is known as a waterspout.
The UK regularly sees bouts of unstable, showery weather throughout the year during every season.
Funnel clouds are not an uncommon weather phenomenon right across the country.
People who have observed a funnel cloud passing overhead have described the sound as similar to buzzing bees or a rushing waterfall-like sound.