This photograph shows forked lightning traveling from cloud-to-cloud.
Photograph courtesy of Gene Rhoden at Weatherpix.com

Forked Lightning- Forked lightning is one of the most visible parts of a thunderstorm. The lightning stroke is branched and usually follows a zigzagging pattern. Forked lightning can go from cloud-to-ground, cloud-to-cloud, or cloud-to-air. The lightning mostly travels from cloud-to-cloud and only goes from the cloud to the ground 20% of the time. Cloud-to-air is the most uncommon form of forked lightning, but when it does happen it may appear that the lightning appears from no where if the sky above the cloud is clear and the lightning may reach up to ten miles away from the cloud.

Streak lightning- is very similar to forked lightning. It follows the same zigzag formation, but it doesn’t have any branches.

Heat Lightning- Heat lightning, like sheet lightning, occurs within a cloud, but the observer is too far away from the storm to hear the thunder. Observers have to be at least a distance of ten miles away from the storm to not hear the thunder, but they can be a distance of five miles away, because tall buildings and trees can distort the sound. Heat lightning is most often seen on hot summer nights, because the sky around you might be clear, but in the distance a thunderstorm might be visible.

Ball Lightning- This extremely rare form of lightning takes the form of a slow moving sphere. It is usually less than three feet wide or around the size of a basketball and people have reported it being many different colors, including blue, yellow, and a pinkish orange. These spheres of lightning usually occur during a violent thunderstorm after a previous flash of lightning. Ball lightning can last for several seconds, to several minutes, but in the amount of time very little damage is reported due to ball lightning and no deaths. Witnesses have reported ball lightning breaking a window or entering their house through a screen. Some witnesses say that ball lightning broke through a screen or window and slowly floated in their house until it vanishes or leaves through a different window. Other witnesses say that they saw it slowly falling from the sky and disappearing before it hits the ground. Since there is no proof that ball lightning really exists, except a few photographs or eyewitness accounts, some scientists are skeptical about if it is really real or just an illusion. Others believe that it is possible for ball lightning to exists, backing their selves up with the damage reports and even drawings and reports made by ancient people who have seen sphere shaped lightning falling out of the sky.

Saint Elmo’s Fire- Saint Elmo’s Fire isn’t actually a form of lightning, but an electrical discharge, which forms above tall pointy objects above the ground, like the masts of ships, power poles, and airplane wings. This form of lightning gives off a bright bluish greenish glow. Its made from tiny sparks, which are positively charged, heading upwards, because the growing negative charge in the clouds above. Instead of lightning forming the “corona discharge” tries to get away from the object that it is near, causing the glow.

High-altitude Lightning- The three forms of high-altitude lightning were recently discovered. They take place above the clouds, shooting upwards, while the cloud gives off a lightning discharge. The three types of high-altitude lightning are red sprites, blue jets, and green elves. Red sprites take the shape of a carrot and occur in the middle of the atmosphere. Blue jets are very small streaks of lightning with flared ends and green elves are a barely visible form of high-altitude lightning that spreads across the atmosphere and looks similar to a jellyfish.