In the spirit of weather watches and warnings, the National Weather Service is testing a new alert system for dangerous heat conditions.
The HeatRisk tool is an “experimental color-numeric-based index that provides a forecast risk of heat-related impacts to occur over a 24-hour period,” according to the organization.
The weather service has a five-point HeatRisk scale, with numbers and colors:
— 0 or green: Little to no risk from expected heat
— 1 or yellow: Minor risk
— 2 or orange: Moderate risk
— 3 or red: Major health risk from hot weather
— 4 or magenta: Extreme conditions. This rating should be used rarely, the weather service said.
The weather service acknowledges it gets hot in the summer, so this tool is beyond that. It attempts to flag conditions that are unusually hot for the time of year. For example, will it be warmer than the highest recorded temperatures for a day or a week? The scale also factors in humidity, which can increase risk of health issues, or the presence of unusually warm overnight temperatures.
Chattanooga’s forecast of mid-90s on Saturday is flagged orange with moderate risk. Sunday, however, shows parts of Chattanooga and the surrounding region experiencing a major risk.
Local3 Weather forecasts a high of 96 Sunday with a chance of isolated storms.
Staff writer Shelby Farmer contributed to this report.