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Woman, is this possible?
Apparently it is, and not only possible but also very common. Small sized and young hatchlings use a practice called ballooning for a free ride. It is thought that spiders weighing under 1 mg can successfully use this technique, but heavier ones (more than 100 mg) have been observed in hot days flying with the help of thermals (updrafts of hot air that being lighter start elevating higher in the atmosphere).
Ballooning? Did they get balloons from It?
No, they didn't. Spiders just get on a high point, like a fence pole for example, point up with their abdomens and shoot strands of silk in the air. They weave kind of DIY parachutes and when there is a current blowing, it takes them away lifting them up and landing them a few meters or even hundreds of kilometers further. It is a technique that lots of insects use for dispersal and it's probably the reason why every continent has spiders and why in every land formed by volcanic activity spiders are the primary dwellers.
Why do spiders do it?
Because they could not afford Ryanair... kidding. Insects use ballooning or kiting very often individually under our nose. But under certain circumstances it is possible that they do it as a whole colony or because weather conditions lead them to. If, for example, a great number of insects were ready to take off at different times but the wind was not perfect and they had to wait, then when the breeze needed to lift them up is ready, it takes all of them at the same time. It is then that the name Spider Rain is justified.
Other possible reasons are environmental conditions like floods and wild fires. When water levels rise, spiders climb to the tallest point possible and wait for the wind to get them to safety. The same happens when they need to escape a fire that threats to burn them alive. In either case it's fly or you die.
Am I gonna die?
No, species of venomous spiders that are dangerous for humans are rare; and even if such spiders were floating around, it would be their youngs that would be able to travel (being smaller and lighter). This means that the flying travellers wouldn't be able to bite.
People are not going to die but crops might. You see, when thousands of spiders decide to take off, their landing place is covered in thick layers of silky spider web. This means that crops might perish burried beneath the webs, unable to get the valuable sunlight. This is what gave the phenomenon a second name, Angel Hair.
Every web, er sorry, cloud has a silver lining though, because those insects are the perfect snack for birds. Imagine being a bird flying in the sky. Thinking how hungry you are and how nice it would be to have some tasty, freshly cooked insects. And the very moment you are having this thought, you open your mouth and a poor little flying spider ends up to satisfy your hunger. Lucky you!
Places arachnophobes should avoid
Phenomena of spider rain are not rare in Australia. In Southern Tablelands the ground was covered in spiderweb in 2015. The same happened in the countryside of Wagga Wagga in 2012. Similar events have occurred in Memphis, Tenessee in 2015, in the UK, Brazil and Pakistan.
Conclusion
My dear
But you can always visit beautiful Greece, 
References
nationalgeographic.com
iflscience.com
livescience.com
todayifoundout.com
wikipedia.org
Thank you so much for your time!
Below you can find some of my recent posts:
- The Diamond Chaser - A Short Story Of Fiction
- 5 Things You Would Boss Yourself To Do (A Revenge Challenge)
- Trolls Around The Solar System (Part 5 - Jupiter)
- Bizarre Natural Phenomena Vol. 38 - A Hole In The Water (The Great Blue Hole)
Until my next post,
Steem on and keep smiling, people!
