Tuesday's high temperature is expected to be 103 degrees, and temperatures are expected to hit the triple digits through Saturday.
O'Leary said it might seem unusual to guzzle water hours before you start outside activity or carry water with you wherever you go, but such measures aren't overly cautious.
“Oklahomans are groomed to think we can handle these extreme temperatures,” O'Leary said. “But this isn't necessarily what we're used to. This heat wave is extraordinary, and it requires extraordinary behavior.”
EMSA paramedics have responded to about 150 heat calls since June 17, when they issued their first heat alert of the year.
Most patients begin to improve when they are taken out of the heat and given cool packs and intravenous fluid in a cool ambulance. Some need more treatment at a hospital.