Stormy weather means high winds and heavy rain or snow. In some parts of the world, the extremely fast-moving winds of hurricanes and tornadoes may be powerful enough to cause severe damage and even loss of life. Heavy rainfall or blizzards often also result in floods or mudslides. They may cause avalanches in mountainous areas.

Lightning

Thunderclouds form when warm, moist air rises quickly. As water droplets and ice crystals in the air bump together, they produce electricity. We see this as lightning. The heat of the lightning flash causes the air around it to expand rapidly, making the boom of thunder.

A hurricane (known as a typhoon in the Pacific, or a tropical cyclone in the Indian Ocean) is a storm that occurs in tropical regions. It begins when warm, moist air rises high above the oceans. The air begins to swirl around in a spiral. Clouds form and massive downpours follow. Very powerful winds rage around a calm centre, called the “eye” of the storm. When a hurricane moves across land, it can cause great damage, ripping up trees and overturning cars. Flooding often results from a hurricane.

Tornadoes

A tornado is a twisting column of air, swirling at up to 400 km/h (250 mph). Its base may be only 100 metres (300 feet) across, but the winds are so powerful they destroy nearly everything in their path. Many tornadoes occur in the US Midwest, but they are also quite common elsewhere—including the UK. A tornado usually forms at the back of a thunder-cloud. A twisting, funnel-shaped column of air grows downwards from the cloud.