What causes flash floods and the floods that took place this summer in Poland?

Flash floods are floods that happen very fast and with little warning. They are very dangerous. A heavy rain or an accident like a dam breaking can cause one.

Sometimes the ground can't soak up water. The water doesn't have any place to go but downstream. Sometimes a city at the base of a mountain can get hit by a flash flood even if it's sunny because the rain can come down the mountain.

Dams are made to hold a lot of water. They block rivers so people can have water. If a dam were to break, then all that water would rush down the river and cause a flash flood.

The floods in Poland this summer were a different kind of flooding. The ground was full of water because the area had gotten a lot of rain. Then one Saturday it began to rain again and didn't stop for a long time. By Monday areas were beginning to flood. If you want to know more about the flood in Poland, check here.

What causes flash floods and the floods that took place this summer in Poland?

Flash floods are floods that happen very suddenly and with little warning. They are very dangerous. A very heavy rain or an accident like a dam break can cause one.

Sometimes the ground is too hard or too wet to soak up water. The only place the rain can go is downstream. Usually rainfall of more than one inch in one hour is needed to cause a flash flood. Sometimes a place can get hit by a flash flood even if it's sunny because it might be raining on higher ground somewhere.

Dams are designed to hold a river's water in reserve for when people may need it. If a dam were to break then all the trapped water would rush down the river at the same time and cause a flash flood.

The floods in Poland this summer weren't flash floods. They were caused by heavy rainfall but the rain was spread out over days. So much rain fell that the rivers couldn't handle all the water. If you want to know more about the flood in Poland, check here.

Sometimes these kinds of floods can be forecast so people can plan ahead. One cause of floods can be forecast months in advance--snow. Melting snow can cause dangerous floods like what happened this spring in the upper-midwest U.S.

What causes flash floods and the floods that took place this summer in Poland?

Flash floods occur very suddenly with little advance warning and can be very dangerous. The are usually caused by a sudden downpour or by an accident like a dam breaking.

Sometimes the ground is too hard or too wet to absorb water. That means that all the rain must travel downstream. Usually at least one inch of rain in an hour is needed to cause a flash flood. Sometimes an area can get hit by a flash flood even if it's sunny and hasn't rained because it might be pouring rain on higher ground somewhere.

Dams are designed to hold a river's water in reserve for when people may need it. If a dam were to break, then all the water in the reservoir would rush down the river at the same time causing a flash flood.

The floods in Poland and central Europe this summer were caused by heavy rainfall but weren't flash floods. A heavy rain was spread out over days and the rivers weren't able to handle that much water. If you want to know more about the flood in Poland, check here.

Sometimes these kinds of floods can be forecast so people can try and protect themselves or evacuate. One cause of floods can be forecast months in advance--snow. Melting snow can cause dangerous floods like what happened this spring in the upper-midwest U.S.

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