Weather service tests new heat stress index

SHREVEPORT, La. -- The National Weather Service is testing a new system of heat stress advisories to provide earlier warnings for people vulnerable to oppressive heat and humidity.

The tests are being conducted only in the agency's southern region, but if it works well the alert system could be expanded to the National Weather Service nationally, said Lee Harrison, head of the Shreveport office.

The weather service will continue to use the heat index, a number based on a combination of temperature and humidity. Under that system, an advisory is issued when the heat index is likely to reach 105 degrees by day and 80 degrees at night over a 48-hour period.

The weather service said the trial system, which takes effect Monday, will expand the advisory into three categories.