Summer has hit Northwest Oklahoma with a vengeance this week.

An excessive heat warning was instituted Wednesday by National Weather Service, and another such warning is in effect 11 a.m. to 8 p.m. today.

High temperatures will be above 100, with heat index values climbing to dangerous levels.

“Take extra precautions if you work or spend time outside. When possible, reschedule strenuous activities to early morning or evening,” according to the NWS warning.

“Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose fitting clothing when possible and drink plenty of water.”

Signs and symptoms of heat exhaustion may develop suddenly or over time, especially with prolonged periods of exercise. Heat exhaustion symptoms include cool, moist skin with goose bumps when in the heat, heavy sweating, faintness, dizziness, fatigue, weak and rapid pulse, low blood pressure upon standing, muscle cramps, nausea and headache.

Heat stroke symptoms include a core body temperature above 104 degrees but fainting may be the first sign.

Other symptoms may include throbbing headache; dizziness and light-headedness; lack of sweating despite the heat; red, hot and dry skin; muscle weakness or cramps; nausea and vomiting; rapid heartbeat, which may be either strong or weak; rapid, shallow breathing; behavioral changes such as confusion, disorientation or staggering; and seizures and unconsciousness.

Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency, call 911.

It’s also vitally important to remember to not leave children and pets in vehicles during this heat.

According to NWS, the temperature inside a vehicle can turn deadly in a matter of minutes.

For example, if the outside temperature is 80 degrees the temperature inside the vehicle can reach 109 degrees in 20 minutes.

If at all possible, stay in an air-conditioned room and stay out of the sun.

Also remember to check up on relatives and neighbors to make sure they are OK.

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