TAMPA, Fla. (WFLA) — A relentless heat wave has continued in states across the eastern half of the country.

Millions of Americans are now feeling dangerous heat that can lead to heat exhaustion or heat stroke if proper precautions are not taken.

The heat dome gripping the southeast will slide west and expand over the plains this weekend. Next week, it is forecast to move back east with dangerous heat continuing.

Long exposure to temperatures this warm can allow heat exhaustion to set in. If not treated, the exhaustion can lead to heat stroke.

Heat is the number one killer in the 10 and 30 year weather-related fatality averages. Take the heat seriously.

Signs of heat exhaustion include dizziness, thirst, heavy sweating, nausea and weakness. If you are or see anyone with these symptoms act quickly and move to a cooler area. Loosen any tight clothing and sip cool water.

If you start to experience dizziness, confusion or you see someone become unconscious, call 911 immediately. Move to a cooler area right away, loosen all clothing and remove any extra layers. Attempt to cool off with water or even ice. Heat stroke is extremely serious and can cause permanent disability or death if medical treatment is not given immediately.

Above average temperatures are expected for the majority of the country for at least the next two weeks.