* WHAT...Dangerously hot conditions, with temperatures around 104 to 108 expected.
* WHERE...Marble and Glen Canyons and Oak Creek and Sycamore Canyons.
* WHEN...From 10 AM MST /11 AM MDT/ Friday to 8 PM MST /9 PM MDT/ Sunday.
* IMPACTS...Most individuals will be at risk for heat-related illnesses without effective cooling or adequate hydration, especially with prolonged outdoor exposure.