Is it really possible for frogs to fall from the sky?

While it’s unlikely you’ve experienced such a shocking sight, other people have. Imagine driving in a storm, only to realize the hailstones hitting your car are actually frozen frogs. Though it’s not something you encounter every day, it’s not as uncommon as you might think. This phenomenon has been recorded since the first century A.D., when the Roman naturalist Pliny the Elder documented it, and even as recently as 2005 in Serbia.

Reports of frogs — and even other surprising objects — raining from the sky seem to pop up every decade or so. In fact, amphibious rain seems to be happening more frequently. Over the past 20 years, newspapers have written more about frogs falling from the sky than ever before. For reasons yet to be fully understood, the UK seems particularly prone to this phenomenon in recent years. The cause of this frog rain is less mysterious, though still puzzling at times. It’s as unsettling as many of us imagine, with the 1999 film "Magnolia" depicting a similar event in a way that left viewers both disgusted and impressed. And, according to various reports, that scene was surprisingly accurate.

In this article, we’ll uncover the science behind frogs falling from the sky and explore what happens when this unusual event occurs. Incidentally, frogs aren’t the most typical creatures to rain down — but we’ll understand why when we examine the mechanics of frog rain on the next page.

Our first question is a simple one: How do frogs end up in the sky in the first place?

What Causes Frog Rain: The Flight of Amphibians

It's hard to imagine frog rain without picturing Moses in the background. The iconic image of a slimy, unexpected flood of frogs is hard to shake. But there’s actually a simple explanation behind it: It all comes down to whirlwinds and lightweight creatures.

Frogs can weigh as little as a few ounces. Even the heavier ones don’t stand a chance against a waterspout, or a whirlwind that picks up water. The sequence of events leading to frog rain is pretty straightforward:

A small tornado forms over a body of water. This type of tornado is called a waterspout, typically triggered by the high-pressure system that precedes a severe thunderstorm.

Similar to a land-based tornado, the center of a waterspout is a low-pressure tunnel surrounded by a high-pressure cone. This is why it pulls in lightweight objects like cows, trailer homes, and cars. But since a waterspout forms over water, it's not cars that get swept up, but water and sea creatures.

As the waterspout moves across the water, it pulls in lighter objects from the surface. Frogs, being lightweight, get caught up in the vortex, which continues to travel with the high-pressure storm clouds. If the storm is strong enough, the waterspout may follow it as it moves onto land.

When the storm hits land, the waterspout loses energy and begins to slow down. The pressure drops, and the clouds eventually release the water they were carrying. As the rain falls, the vortex loses the pressure keeping it active and releases everything it has collected during its journey. Sometimes, that includes frogs.

The end result is frog rain. It could be just a few frogs, a couple hundred, or even thousands. And it’s usually not just frogs. While frogs get the most attention because of their biblical appearance in Exodus, waterspouts can carry a variety of objects. So, what’s the strangest thing that can fall from the sky? Find out next.

Other Weather Oddities: It’s Raining Tomatoes

Frogs can travel astonishing distances within the vortex of a waterspout. Though it’s rare for them to travel hundreds or thousands of miles, it’s more common for frogs to travel only a few miles before descending back to the ground.

Strange objects falling from the sky are not uncommon, with reports of squid, worms, and fish raining down. Fish are the most common, given their light weight and prevalence in aquatic environments [source: BBC]. However, waterspouts are also capable of lifting heavier objects.

Waterspout winds can reach incredible speeds — up to 200 mph [source: CMMAP]. Such wind forces can lift a wide range of objects, sucking them up from as deep as 3 feet (1 meter) below the water’s surface. The low-pressure core within these winds acts as a powerful vacuum. Large birds and even sailboats have been reported falling from the sky. Waterspouts have also been known to bring down tomatoes and coal when they hit land [source: CMMAP].

The real unpleasantness happens when frogs, fish, and other aquatic creatures hit the ground. It’s unlikely they survive the journey, considering the intense speed of the low-pressure vortex and the impact once it dissipates. Typically, the frogs don’t make it, though it’s unclear exactly when they die — during the ride or as a result of the fall.

However, sometimes the frogs catch a lucky break. In 2005, when frogs rained down on a small Serbian town, locals emerged after the storm to find their streets covered in frogs, all trying to hop their way back to the water.