Hoosiers could face danger from excessive heat and humidity next week as forecasters are predicting a massive heat wave covering all of Indiana.

The National Weather Service in Indianapolis issued an 8- to 14-day temperature outlook calling for a 90-100% chance of above-normal temperatures beginning Tuesday as the heat covers most of the Great Lakes region.

“Looking ahead, confidence is growing that next week will see the hottest temperatures thus far this year to go along with humid conditions,” the advisory says.

Indianapolis has already seen record-breaking heat this spring and last year was the warmest year recorded in NOAA’s 174-year global climate record “by a long shot.”

NOAA’s chief scientist, Sarah Kapnick, says records will continue to be broken and extreme weather events will grow until emissions are reduced and climate resilience is built.

Indiana will face a major risk of heat-related impacts beginning Monday, according to NWS, which means it can affect “anyone without effective cooling and/or adequate hydration.” A rare risk of extreme impacts might hit portions of Northwest and Central Indiana on Tuesday, meaning there could be no overnight relief from the heat.

Current forecast: Central Indiana poised for humid, 90-degree temps this week as first hot swell approaches

How to stay safe during a heat risk

Older Hoosiers and young children are most at risk during extreme heat events. To stay safe and prepared, here’s what the experts suggest:

The American Red Cross

• Stay hydrated and avoid sugary, caffeinated and alcoholic drinks
• Electric fans may not provide relief, instead take a cooling shower or bath and find an air-conditioned space

The National Weather Service

• Reduce, eliminate or reschedule strenuous outdoor activities
• Eat light, cool, easy-to-digest foods like fruits or salad

Centers for Disease Control and Prevention

• Choose lightweight, loose-fitting clothes
• Head to a public library or other space with air conditioning

What are the signs of heat-related illness?

Three main heat-related illnesses to be on the lookout for are heat cramps, heat exhaustion and heat stroke. If any of the following symptoms are evident on you or another person: move to a cooler area, loosen any clothing and sip cool water. Seek a medical professional if any of the symptoms don’t improve within an hour.

Heat cramps may be the first sign of illness that could lead to more serious symptoms. Cramps shows up as painful muscle cramps or spasms along with heavy sweating, according to NWS. Use firm pressure on the cramping muscles and massage them gently.

Heat exhaustion will show up as heavy sweating, weakness or tiredness with cool and clammy skin. The person’s pulse may be quick but weak and they may exhibit dizziness or nausea. Immediately move the person to an air-conditioned room, loosen clothing and apply cool, wet cloth to the skin.

Heat stroke needs immediate medical attention, so call 9-1-1- or get the patient to a hospital. Heat stroke can appear as throbbing headaches, confusion, nausea, dizziness, body temperatures above 103 degrees. The patient’s skin can also appear red with a lack of sweat. This is a serious illness and delays in medical care can be fatal.

Karl Schneider is an IndyStar environment reporter. You can reach him at karl.schneider@indystar.com. Follow him on Twitter @karlstartswithk

IndyStar’s environmental reporting project is made possible through the generous support of the nonprofit Nina Mason Pulliam Charitable Trust.