A 500-year flood means such an event has a 1 in 500 chance, or 0.2 percent, of occurring in a year. Another concept scientists use is how frequently an event of a certain intensity is expected.

If you live in a 1-percent AEP (100-year) flood zone, writes USGS, the odds of being flooded at least once over a 30-year mortgage are 26%. That's about a 1 in 4 chance.

What does a 100-year flood mean? Scientists use math to help people understand how unusual a severe flood is and how to compare the intensity of one flood to another.

A 500-year flood means such an event has a 1 in 500 chance, or 0.2%, of occurring in a year. Another concept scientists use is how frequently an event of a certain intensity is expected.

Understanding the term '100-year flood' We’ve all heard the term “100-year flood” — but it might not mean what you think. To stream WFMY News 2 on your phone, you need the WFMY News 2 app.

A 500-year flood means such an event has a 1 in 500 chance, or 0.2%, of occurring in a year. Another concept scientists use is how frequently an event of a certain intensity is expected.

According to the U.S. Geological Survey, one statistic scientists use is the percentage chance that a flood of a specific magnitude will happen.A 500-year flood means such an event has a 1 in 500 ...

This is what forecasters mean when they talk about a 100-year flood. AP FILE - Cars are submerged on a freeway flooded in the aftermath of Hurricane Harvey near downtown Houston.

What does a 100-year flood mean? Scientists use math to help people understand how unusual a severe flood is and how to compare the intensity of one flood to another.

A 500-year flood means such an event has a 1 in 500 chance, or 0.2%, of occurring in a year. Another concept scientists use is how frequently an event of a certain intensity is expected.