We all have heard of water spouts, dust devils, and tornadoes, but what about a firenado? The fire whirl is a rare occurrence in which a fire forms a tornado-like vortex of flames. These vicious cyclones of flame are also known as firenadoes or fire devils and no wonder – these babies look like they come straight out of the deepest bowels of hell!
These hellish whirling dervishes of fire occur when trees, a hillside or flames force air to shift against competing air temperatures and speeds. While some fire whirls peter out pretty quickly, others can travel when the heat is able to stay afloat and surrounding gasses push it tighter onto itself.
If you don’t care for a spiraling inferno, how about a fire rainbow? Technically known as a circumhorizontal arc, conditions have to be very precise for these rainbows to occur. They usually occur during the summer months – the sun has to be at an elevation of 58° or greater with high altitude cirrus clouds and sunlight entering the ice crystals of the clouds at just the right angle. Also known as an ice halo, the circumhorizontal arc is actually neither fire nor a rainbow, pretty cool right?
Another truly fascinating and rare weather phenomenon is volcanic lightning, otherwise known as a dirty thunderstorm. Not only do you have the menacing appearance and danger of a volcano erupting, but add lightning to the mix and you’ve got one spine-chilling weather wonder! Volcanic lightning occurs when lightning is produced in a volcanic plume. The process starts when particles separate, either after a collision or when a larger particle breaks in two. Some difference in the aerodynamics of these particles then causes the positively charged particles to separate from the negatively charged particles. Lightning occurs when this charge separation becomes too great for air to resist the flow of electricity. Volcanic eruptions also release large amounts of water, which can also help these thunderstorms along.
Last but not least, for all of the cloud lovers out there, let’s take a look at one of the coolest weather phenomenon out there….roll clouds! Some have described these clouds as looking like toppled tornadoes. These types of arcus clouds are typically associated with thunderstorms. Not to be confused with the similar shelf cloud, these rarities of nature occur when air temperatures invert and cause the warm air to be on top of the cool air. Wind then changes speed and direction and causes a rolling effect of these cylinder-type clouds. Roll clouds need just the right amount of moisture to occur. The storm winds actually push the clouds into a tubular shape, which moves them ahead of the storm. They look like a giant rolling pin across the sky! Roll clouds and mammatus clouds seem to be a very rare, but very popular item in the weather community. What are some of your favorite, but weird weather phenomenons? Let us know!