GLASGOW, Ky. — Dangerous heat will last longer than initially expected, with an Extreme Heat Warning now extended through Friday evening, according to the National Weather Service.

The warning, issued by the National Weather Service in Louisville, now remains in effect until 8 p.m. CDT Friday, extending the previous end time that had been set for Thursday.

Heat index values are expected to range between 100 and 115 degrees across south-central Kentucky and surrounding areas, including Barren County. Overnight temperatures are also expected to remain warm and humid, offering little relief from daytime conditions.

Officials warn that the prolonged period of extreme heat significantly increases the risk of heat-related illness.

“Heat related illnesses increase significantly during extreme heat and high humidity events,” the Weather Service said in its advisory.

Residents are urged to take precautions, including staying hydrated, remaining in air-conditioned spaces when possible, avoiding prolonged outdoor activity during peak heat hours, and checking on vulnerable neighbors.

Officials also warn against leaving children or pets in vehicles, noting that interior temperatures can become dangerous within minutes.

The warning covers much of south-central Indiana and a large portion of Kentucky, including Barren County and surrounding communities.