Red Sprites (and Elves)

Red sprites are a type of transient luminous event (TLE) that occurs above intense thunderstorms. They appear as giant electrical discharges, often reddish or orange in colour, above the storm clouds (cumulonimbus).

These phenomena are triggered by powerful positive electrical discharges between the top of the cloud and the ionosphere, at altitudes between 50 and 90 km. Their duration is extremely short, generally just a few milliseconds, which makes them difficult to observe with the naked eye.

Red sprites are generally associated with mesoscale convective systems (MCS). Observing them is favoured by conditions of low ambient light (night or twilight) and a clear horizon.

Red sprites mainly form when strong positive electrical discharges (known as CG+, or positive cloud-to-ground lightning) occur between the top of the cloud and the ground. These discharges generate an intense electric field above the storm, which ionises the air and creates a cold plasma discharge propagating upward: the sprite. The ambient electrons are accelerated, collide with local gas molecules and excite them. As these molecules return to their normal state, they emit light.

Red sprites are difficult to capture because of their brief duration and low luminosity. If you'd like to get hands-on, check out the complete field guides for photographing red sprites. Here are a few essential tips to get you started:

Tip: Use automatic detection software (such as UFO Analyzer) to analyse your videos and spot sprites.

Red sprites above a storm near Florence, from Fréjus Saint-Raphaël 25/08/2026 - © 2026 Christophe Suarez

To learn more about red sprites, here are a few interesting links: