In a typical year, the United States can expect 1,000 tornadoes. The chart shows tornado warning lead times increasing from 6 to 11 minutes from FY 1994 to FY 1999 (proj). This means that individuals and communities have more time to prepare for tornadoes by securing property and seeking shelter, thereby limiting the economic cost of property damage and reducing the loss of life
Flash floods are the number one weather related killer in the United States. Flash floods occur within a few minutes or hours of excessive rainfall, a dam or levee failure, or a sudden release of water held by an ice jam. Lead times for flash floods have increased from 18 to 42 minutes over the past four years. This means that communities have more time to evacuate people in the flood zone, thereby reducing the loss of life.