New Delhi, June 22 -- Visitors to Grand Canyon National Park are being warned about extreme temperatures that will hit the popular destination early next week after a recent increase in heat-related incidents in the inner canyon, including the deaths of three hikers.

The National Weather Service issued an extreme heat watch at the Grand Canyon for midday Monday through Tuesday, forecasting temperatures that could reach or exceed 110 degrees Fahrenheit (43 degrees Celsius) at the low-elevation Phantom Ranch.

People are "strongly advised" to avoid hiking in the middle of the day, the National Park Service said this week in a statement following a "recent influx of heat-related incidents."

An extreme heat watch was in effect June 16 when ...