Heat is the number-one weather-related killer in the United States. On average, over 200 people die each year in the U.S. due to excessive heat. This number nearly equals the annual number of deaths due to tornadoes, hurricanes, floods, and lightning combined.

In an effort to better address this potential threat, while providing more effective information on heat-related impacts to the public, the National Weather Service forecast office in Huntsville is adopting new criteria for excessive heat events. These changes are now in effect.

Heat Advisory: Heat Indices are forecast to be between 105-110°F, and/or actual air temperatures are forecast to be between 100-105°F.

Excessive Heat Warning: Heat Indices are forecast to exceed 110°F, and/or actual air temperatures are forecast to exceed 105°F.

Additional heat related information, including safety and preparedness tips, can be found at http://www.weather.gov/om/heat/index.shtml.