A patch of trees curved in a “J” is a sign of an approaching landslide. The trees grow into this shape due to the soil creep, a slow ground movement that indicates the overall instability of a slope. Encountering trees like this does not mean you’ll be facing an immediate disaster, only that a landslide has happened there before and will likely happen there again at some point.

You may have seen the sky turn this sickly shade of green. The view is totally apocalyptic, but it’s actually a rather common sign of powerful thunderstorms. Thunderstorms occur mostly in the evening, when the sun’s blue light, which we mostly see during the day, is intermingling with red light, visible during sunsets. The result, filtered through heavy clouds, is a green color in the sky.

When you see a weird, perfectly-square wave pattern in the sea, more than likely there’s a rip current lurking beneath the water’s surface. And they’re immensely dangerous. Rip currents are responsible for the death of over 100 people yearly in the U.S. This pattern occurs when 2 current systems run into each other — or when the wind pushes waves in one direction and the underwater current pushes them in another.

When animals collectively decide to hit the road all of a sudden, this can be a signal of an earthquake. Animals might also exhibit strange behavior and restlessness. The closer they are to the seismic center, the earlier they understand that something is wrong. There are a few theories on how exactly animals sense an oncoming quake, which may include air ionization or the smell of gases released before an eruption.

If you feel your hair standing up all over your body, send your regards to the impending thunderstorm and lightning. Lightning strikes only after a charge buildup, and sometimes people can feel this buildup when it is happening nearby. People also experience a slight buzzing around metal accessories and a tingling feeling on the skin, while the hair’s ends can literally stand up and reach for the sky.

Wall clouds are large, dense clouds that sit low and spread up to 5 miles long. They’re formed when the warm moist air rapidly rises and displaces the cooler wet air above, making the pressure drop. If the cloud starts rotating, it can create a tornado. Similarly, cone-shaped funnel clouds can cause a tornado as well if their cone touches the ground.

Sometimes you might witness a light halo around the sun and moon. These rings are actually thin cirrus clouds, made up of tiny ice particles. Sunlight is split and reflected through these crystals, so we can see it as an actual halo. And, like rainbows, sun rings are personal — everyone sees their own unique pattern of light! But high cirrus clouds often come before a storm, which is especially true for lunar halos.

If you’re on the beach and the water suddenly withdraws, a tsunami is likely on the way. Tsunamis occur due to a powerful earthquake or some other kind of explosion somewhere on the ocean floor. They can travel extremely fast — about 500 miles per hour — so you probably won’t see an approaching wave. But it will expose a wide part of the ocean floor that is not normally visible, even at low tide.

If you see animals and birds running and flying toward you, there might be a wildfire behind them. Fleeing and hiding are survival strategies for wildlife and it’s trying to make the best of it. Smoke, hot air, and a burning smell are also solid signs of fires.

Imagine yourself going skiing or hiking in the winter. You’re checking to see if the snow feels hollow to you or if you hear a specific “whumpfing” sound underfoot. And most of all — if there are cracks in the snow. All of these things can signal an oncoming avalanche. These cracks mean that the snow is slowly sliding down. Snow can travel faster than 200 miles per hour and is extremely difficult to escape from.

Every once in a while, people might notice uneven flares along the sun’s contour. These sun rays are often accompanied by strong auroras all around the world and are a sign of a solar storm. It’s caused by disturbances in the sun’s magnetic field: the bursts of radiation and gas on the sun’s surface are so massive that they can even reach us on earth.