Extreme heat is in the forecast for New Hampshire, here's how to stay safe

Another bout of extreme heat is on the horizon for New Hampshire.

Climate change is making New Hampshire hotter, and scientists expect more days of extreme heat as the burning of fossil fuels continues warming up the atmosphere.

Extreme heat can be dangerous

Across the country, the Centers for Disease Control and Prevention says more than 600 people die annually from extreme heat. In New Hampshire, a 2021 report from the Granite State News Collaborative found that more than 1,400 residents went to the ER for heat-related illness between 2012 and 2019.

Heat can have harmful effects on anyone, but some people are at even greater risk. According to the CDC, that includes older adults, young children, people with chronic medical conditions, low-income populations, athletes and people who work outdoors. Heat can also be especially dangerous to pregnant people.

Dizziness, nausea, hot skin and a rapid pulse are some of the signs of heat stroke. Heavy sweating, fainting, dizziness and headaches are some symptoms of heat exhaustion.

To stay safe during a heat wave, emergency preparedness officials advise avoiding the outdoors and sun exposure as much as possible, limiting outdoor work and sun exposure during the hottest parts of the day, and wearing loose-fitting and lightweight clothing. If you must stay inside and don’t have access to air conditioning, they also recommend staying on lower floors because heat rises.

Officials also suggest covering windows that get morning or afternoon sun with drapes, shades or awnings.

If you do need to be active in the heat – if you work outdoors, for example – drink plenty of fluids and pay close attention to how you’re feeling, said Dr. Trevor Eide, the medical director for the emergency department at Portsmouth Regional Hospital.

“Any headaches, fatigue, dry mouth, thirst suggest people should stop at that point [and go inside to cool off] – as opposed to continuing to progress until symptoms become worse,” he said.

More from this section

New Hampshire's Halloween sweet tooth: 2025 candy and decor trends from Instacart data

Movies and TV shows casting in Portsmouth

If you notice more serious symptoms – including altered mental status, confusion, slurred speech or continuing to sweat heavily despite moving to a cooler location – it’s a good idea to seek medical attention, Eide said. Those could be signs of heat stroke, a more serious illness than heat exhaustion.

“That all suggests that the body is no longer able to compensate for the increase in heat,” he said.

Eide said older adults are especially vulnerable to heat-related illness and should have air conditioning in at least part of their home – ideally the bedroom, so the body has time to cool off overnight.

State security and emergency management officials also urge people to avoid leaving children or pets unattended in closed vehicles, even with the windows down.

If you don’t have access to air conditioning or if your home loses power, you might be able to go to a local cooling center or find an air-conditioned public space, like a library. You can call your local city or town hall for more information.

More resources

• Call 211 for a list of cooling centers
• Heat waves can also place stress on the electricity grid, reduce energy usage on hotter days

•••

Editor's note: A version of this story was originally published in 2022. It has been updated several times since, most recently on Aug. 11, 2025.

These articles are being shared by partners in the Granite State News Collaborative. For more information, visit collaborativenh.org.