1. St. Elmo's Fire
St. Elmo's Fire is a rare and colorful electrical discharge that occurs during thunderstorms. It is characterized by a bright blue or purple glow on the tips of objects, such as church steeples or power lines. The phenomenon affects about 20-30% of thunderstorms worldwide. St. Elmo's Fire has been observed since ancient times and was even mentioned in Homer's Iliad as a sign from the gods.
2. Ball Lightning
Ball lightning is a rare and poorly understood atmospheric electrical phenomenon in which a glowing, floating ball of light is seen during thunderstorms. It can range in size from a few inches to several feet in diameter and has been observed in various parts of the world. The frequency of ball lightning sightings varies greatly by region, with some areas reporting hundreds of sightings per year. Ball lightning remains one of the most mysterious and elusive forms of lightning.
3. Dry Lightning
Dry lightning, also known as "firestorm" or "forest fire," is a type of lightning that strikes during periods of drought and dry conditions. It occurs when a thunderstorm produces lightning without the presence of sufficient moisture in the air to create heavy rainfall. This rare form of lightning has been responsible for devastating wildfires worldwide. Dry lightning has also been linked to numerous fires in various ecosystems.
4. Blue Jet
A blue jet is a rare and intense electrical discharge that originates from the upper atmosphere, typically above 50 km (31 miles) altitude. It can reach temperatures of up to 200°C (392°F), hotter than the surface of the sun. The blue jet is only visible during severe thunderstorms in the tropics and subtropics. This phenomenon was first observed by pilots in the 1950s, but its exact mechanisms remain poorly understood.
5. Morning Glory Cloud
A morning glory cloud is a rare, tubular-shaped cloud that can appear in association with severe thunderstorms or derechos. It forms when a layer of cool air is trapped under a layer of warm air, creating a rolling wave-like effect. The cloud can stretch for hundreds of kilometers and can reach heights of over 10 km (33,000 ft). Morning glory clouds are also known to produce rare and unusual lightning displays.