Temperatures in the 90's coupled with high humidity is bringing warnings from health officials about heat stroke and heat exhaustion.

The combination of high temperatures and humidity was expected to last at least through Friday, making it feel at times like it was over 100 degrees.

The effects of this heat wave are immense as every state in the Lower 48 Sunday except Maine had at least one 90-degree high temperature.

For those who must either work outdoors or have to stay at home, such as the elderly and children, make sure to take the necessary precautions to avoid the dangerous health problems that extreme heat can cause. Drink plenty of fluids and check on pets as well.

The dangers are heat exhaustion and heat stroke.

The American Red Cross says here's what you should look for and tips on treatment.

If you start to get a pain or stiffness in your muscles - that's heat cramps. Get to a cool place, and drink a half glass of cool water every 15 minutes.

Signs of heat exhaustion include, heavy sweating, nausea or vomiting, and dizziness. If you have these symptoms, get out of the heat and apply cool towels to your body. If you can, drink water, but slowly, again a half glass every 15 minutes.

The most severe condition is heat stroke. Symptoms include red, hot skin, a weak pulse and shallow breathing. Heat stroke is life threatening. Call 911 if you see someone with these symptoms.

If you have elderly friends or neighbors make sure to check on them. Be sure they have a fan in their house and are getting plenty of fluids.

Twenty-one states had at least one location reach or surpass the century mark Sunday.

Hottest of all nationally was Death Valley, California, which endured a high temperature of 126 degrees. Records were smashed literally coast-to-coast, as Los Angeles International Airport on the Pacific Ocean reached 88 degrees Sunday, breaking the old record of 87 set in 1954, while on the East Coast, Saint Simons Island, Georgia, tied a record high of 98 degrees, last set in 1976.

An additional five states - Florida, Minnesota, Missouri, Illinois and Montana had at least one location reach 99 degrees.

For some, there will be good news, as a cold front slicing through the Midwest will break up the heat and humidity - at least temporarily.

This front, however, will pack a cruel twist, in that it will bring the potential for severe storms with it from the western and central Great Lakes back into Iowa.

Behind this front, a surge of cooler air will be ushered in; however, high temperatures will at best drop to near normal.