(WWLP) – By definition flash flooding occurs when there is a extremely heavy rainfall over a short period of time.

The intensity of the rain, location of the rainfall, and soil-water content all determine just how quickly flash flooding may occur in a region. Heavy rainfall can turn tranquil streams and rivers into raging torrents. Since flash flooding occurs so quickly, people are caught off-guard, making the situation even more dangerous.

Massachusetts is expecting heavy rainfall over the afternoon and overnight hours, which means flash flooding and flooding of roadways can happen overnight. This is the most dangerous time for flash flooding to occur, since it is harder to determine how deep the water is on the roadways.

Drivers are reminded that if you encounter a flooded roadway, make sure to turn around and don’t drown.