Earth’s Most Unusual Weather Phenomena Explained

There is so much more to weather than your everyday sunshine or rain (depending on where you live). Nature is one of the most fascinating aspects of life and has the power to give us amazing displays of weather phenomena that often looks like magic.

Thankfully, we have scientists and meteorologists who’ve studied these phenomena and have broken it all down. From rainbows caused by the moon to literal balls of lightning, here are some of the wildest and unusual weather phenomena we’ve ever seen.

One sun-related sight can only be seen if you’re standing in the perfect position relative to what causes it…

Moonbow

what does a moonbow look like
Alan Stark/Flickr

We usually see rainbows during the day, when the sun starts to emerge near the end of a rain shower but on rare occasions, you can also see them at night. Moonbows occur just like rainbows do when there is a refraction of light in multiple water droplets caused by rain or a waterfall – the only difference is the light source.

Moonbows can happen when the moon is low and full to almost full. They often appear white since our eyes since it’s harder for our eyes to discern the colors with limited light.

Mirage

what does a mirage look like
Michael Gwyther-Jones/Flickr

On hot, sunny days you’ll usually see what looks like a pool of water in the distance, only for it to disappear the closer you get to it. The good news is you’re not hallucinating – mirages are a naturally-occurring optical illusion.

Mirages happen as a result of the way light is refracted through different air temperatures. Hot air is a lot less dense than cool air, so light is bent towards denser air away from the ground, causing you to see a mirror image of the sky on the ground.

Halo

what does a solar halo look like
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There’s some truth to the saying that a halo around the sun signals the onset of rain. High cirrus clouds come before a storm and it is these types of clouds that contain millions of tiny ice crystals.

Light is refracted and reflected from these ice crystals high in the sky, which causes people to see a halo. Everyone sees their own version of the halo since the ice crystals have to be in the right position with respect to your eye to be able to see it.

Coming up, you might have heard of the Northern Lights but do you know what makes them happen?

Belt Of Venus

what does the belt of venus look like
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If you’ve ever witnessed the pinkish glow that appears between the sky and the horizon then you just laid eyes on the Belt of Venus. The Belt of Venus is an atmospheric phenomenon that usually occurs at dusk or dawn.

The pink glow occurs from reddened light of the sun when it is rising or setting. The light gets back-scattered into the upper atmosphere even though the sun is below the horizon.

Noctilucent Clouds

what do noctilucent clouds look like
Timo Newton-Syms/Flickr

Noctilucent clouds are those that you can see in the night sky with no obvious light source in plain sight. This occurs when ice crystals in the sky are illuminated by the sun that has already set. These clouds may still be in the vicinity of the sun’s light, despite the fact that the observer is not.

People who live in higher altitudes can usually see them during summer months when the sun is below the observer’s horizon.

Auroras

what is the aurora borealis
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Auroras are amazing light shows put on by nature but how exactly are they formed? The auroras occur when electrically-charged particles from the sun come down to the Earth’s atmosphere and collide with natural gases.

Green and rare red auroras are produced by oxygen, while blue and purple ones are caused by nitrogen. People who live closer to the magnetic poles of the northern and southern hemispheres are lucky to see these happen.

Have you ever seen something that looks like it’s on fire during a thunderstorm? This is explained coming up…

Colored Moons

how do colored moons happen
Murray Foubister/Flickr

We’ve all seen the moon take on different hues like red, pink, orange, yellow, and sometimes even blue. The moon itself never changes colors but you’re not just imagining things when you see a huge orange moon just above the horizon.

Colored moons occur during certain times of the year or when dust particles, water droplets, or gases get in the way of the light refracted from the sun.

Mammatus Clouds

how do mammatus clouds form
Michel Filion/Flickr

Ominous, pouch-like clouds that appear around the time of a thunderstorm are called Mammatus Clouds. These clouds are primarily made up of ice and extend hundreds of miles in any direction.

Mammatus clouds are usually hanging out underneath the base of a larger, denser cloud, which is usually why they occur when it rains. They form when cold air sinks down and forms the cloud “pockets,” unlike normal cloud puffs that rise through the convection of warm air.

St. Elmo’s Fire

st elmos fire weather
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You might’ve been alarmed that time you looked out your window and noticed the streetlamp outside appeared to be on fire. No one did anything about it because it wasn’t actually on fire. This happened as a result of a phenomenon called St. Elmo’s Fire.

Named for the patron saint of sailors, this weather phenomenon happens when a pointed object in a strong electrical field in the atmosphere creates a luminous plasma that looks like fire.

Tornadoes aren’t exclusive to land. Soon you’ll see how they can form over bodies of water. But first, see how they can form out of fire on the next slide…

Fire Whirls

how do fire whirls happen
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No one wants to be in the way of a fire whirl. Also called fire devils or fire tornadoes, these can occur when there is a fire. The heat in the area can cause a cyclone or a whirlwind. When it gets close to the flames, the whirlwind itself can look like it is made of fire.

The whirlwind takes on this appearance when flames or ash from the fire gets caught up in it.

Pyrocumulus Clouds

how are pyrocumulus clouds formed
JOSH EDELSON/AFP/Getty Images

Another weather phenomenon caused by fire are pyrocumulus clouds. Also known as fire clouds or flammegenitus, these clouds appear overwhelming and ominous in the sky after a forest fire or volcanic eruption.

This happens when fires burn hot enough to cause a updraft, a strong upward motion of hot air and smoke that accumulates in the atmosphere. The smoke in the air causes the clouds to take on a murky color and can tower up to five miles high.

Waterspout

strange-weather-01
Colin and Sarah Northway/Flickr

If you’ve ever seen a waterspout, it probably looked like Poseidon himself was summoning a column of water from the sea into the clouds. What actually happens in these cases is not as drastic. Small rotating columns of air over the water start working their way upward.

A funnel starts to form with the surrounding water droplets that makes it look like a tornado made out of water. They mostly occur in tropical areas.

Waterspouts look quite similar to virga but are very different. You’ll find out how coming up!

Sun Pillar

how are sun pillars formed
Brocken Inaglory/Wikimedia Commons

It’s not often that you see a pillar of light emanating from the top of the setting sun but when you do, just know that this natural phenomenon occurs because of ice crystals. Sun pillars or light pillars happen when the light of the sun reflects from tiny ice crystals suspended high in the atmosphere.

This is similar to the way halos form around the sun. You can also see light pillars form with the light of the moon.

Non-Aqueous Rain

what is non-aqueous rain
jimjasongo1/Reddit

Is it possible for non-water objects to rain from the sky? Apparently. It may just be a story from the Bible but non-aqueous rains have been known to actually happen throughout history.

Scientists suspect that this rare meteorological phenomenon happens when tornado waterspouts pick up various animals such as frogs, spiders, or fish and carry them for several miles until they fall back down to Earth. Despite numerous reports of this happening throughout history, scientists have yet to witness it themselves.

Virga

what are virga clouds
Kit Case/Flickr

Sometimes there are clouds with streaks falling out of them that suddenly disappear into thin air. This is what happens when rain doesn’t reach the ground and in meteorology, this is called virga.

Rain does have the capability of evaporating miles before it hits the surface of the earth and this is best seen in the desert, where high temperatures can cause the rain to dissipate in mid-air. The term derives from a Latin word meaning “twig” or “branch.”

Coming up is one phenomenon that you can only see for a split-second before it’s gone!

Katabatic Wind

what are katabatic winds
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Several regions of the world are home to very strong winds that occur at certain times of the year. Southern California is often afflicted with the Santa Ana winds, while the Mistral winds occur throughout the Mediterranean.

These strong winds are called Katabatic Winds or drainage winds. They occur when gravity forces high-density winds to slope into a lower elevation. These winds often cause significant damage and can blow up to 18 kilometers per hour.

Fire Rainbow

what is rainbow fire
Jeff Kubina/Flickr

Rainbows are pretty common sights whenever it rains or in wet environments, but have you ever seen a rainbow painted into the sky? These rainbows often look like they’re part of the clouds in the sky and are called “fire rainbows” or “circumhorizontal arcs.”

Circumhorizontal arcs occur when plate-shaped ice crystals suspended in the atmosphere are refracted by the light of the sun, or sometimes the moon. They often occur in the summertime for people who live in mid-altitudes.

Green Ray

how does a green flash happen
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Just before the sun rises or before it officially sets, don’t blink or you might miss the green ray. Also known as the green flash, a distinct green spot appears over the upper rim of the sun’s disk on the horizon. This meteorological phenomenon only occurs of a moment before it goes away.

The conditions have to be just right in order for you to see it and it often happens if the atmosphere causes the light from the sun to separate into different colors.

Ball Lightning

what causes ball lightning
Joe Thomissen/Wikimedia Commons

Just when you thought that lightning couldn’t get any more dangerous than it already is, in comes ball lightning. Glowing, electrical orbs that can be as big as a pea or several meters in diameter often happen during thunderstorms.

They often last longer than a lightning bolt and eventually explode, leaving behind a sulfuric odor. Scientists theorize that the presence of glass generates these balls of fire, but they’ve also been known to be associated with earthquakes.

Fog

how does fog happen
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Most people are familiar with fog, but do you know how it actually forms? When tiny water droplets or ice crystals get suspended in the air near the Earth’s surface, they form fog. This happens when the difference between the air temperature and the dew point is less than 4.5-degrees Fahrenheit.

Fog thickness is determined by the altitude of wherever the fog decides to take place and has affected human activity due to the way it inhibits visibility.