Meanwhile, there is an EXCESSIVE HEAT WATCH out:

Excessive Heat Watch
Updated: Thu Aug-06-15 02:35pm CDT
Effective: Thu Aug-06-15 02:35pm CDT
Expires: Fri Aug-07-15 08:00pm CDT

Severity: Moderate
Urgency: Future
Certainty: Possible

Status: Actual
Type: Alert
Category: Met
Areas affected: Atoka; Bryan; Canadian; Carter; Cleveland; Coal; Garfield; Garvin; Grady; Grant; Hughes; Jefferson; Johnston; Kay; Kingfisher; Lincoln; Logan; Love; Marshall; McClain; Murray; Noble; Oklahoma; Payne; Pontotoc; Pottawatomie; Seminole; Stephens

Instructions: Take extra precautions if you work or spend time outside. When possible...reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear light weight and loose fitting clothing when possible and drink plenty of water. To reduce risk during outdoor work the occupational safety and health administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency...call 9 1 1. Take care of yourself and others to prevent heat related illness.

Message summary: ...heat advisory remains in effect until 8 pm cdt this evening...
...excessive heat watch remains in effect from friday afternoon through friday evening...
The national weather service in norman has issued an excessive heat watch...which is in effect from friday afternoon through friday evening. A heat advisory remains in effect from 1 pm this afternoon to 8 pm cdt this evening. The national weather service in norman has issued a heat advisory...which is in effect from 1 pm to 8 pm cdt thursday.
* heat indices: 108 to 113 degrees friday.
* impacts: heat exhaustion and heat stroke are more likely with high heat indices. Take precautions to prevent heat related illnesses.