OKLAHOMA CITY--- Oklahomans know how to prepare for a blizzard, tornado or severe storms, but officials said many fail to plan for extreme heat.
"The heat is just as dangerous if not more because people aren't prepared,"EMSA's John Graham said.
The triple-digit temperatures are back and health officials said people are getting sick left and right.
EMSA paramedics have responded to almost two dozen heat related calls since Monday.
The National Weather Service issued a heat advisory for the entire state Tuesday which will last until 10 p.m. Friday.
That means everyone who is outside even for just a little while is facing an increased danger of having a heat-related illness, including exhaustion and stroke.
Doctors said dehydration causes the blood to thicken preventing your kidneys from processing waste.
A lack of water also causes a negative change in vital fluids.
"People who are working hard outside today may not see the effects until tomorrow or the next day because there's not going to be any relief from the heat and it will have a cumulative effect," Graham said.
Graham urges people to take extra precaution and get out of the heat quickly if you start to fell ill.
Medics want to remind people to check on elderly relatives and not to leave children or pets in vehicles even for a minute.
"Stay ahead of the curve. If you know you're going to be outside, drink lots and lots and lots of water," Graham said.