To stay safe, make sure you stay hydrated, take frequent breaks in shaded areas and avoid peak afternoon heat, generally between 1 and 5 p.m. (Here's more tips on how to protect yourself during a heat wave.)
Reduced air quality is expected, too, so sensitive groups should consider limiting prolonged outdoor exertion, and maybe head to the nearest beach or river spot instead.
Friday
Friday will be the hottest day of the weekend, as temperatures soar into the mid to upper 90s. Humidity will keep heat indices in excess of 100 degrees on Friday.
Saturday
Expect more widespread showers and thunderstorms Saturday, so keep an eye to the sky, particularly above the treeline. High temperatures will remain in the upper 80s and 90s. Campers shouldn’t expect much nighttime relief, as overnight lows remain in the upper 60s and 70s all weekend.
Sunday
Less rain and more sunshine is expected Sunday, as temperatures begin to moderate.
More resources
NH summers are hotter than ever. Here's how to stay safe.
Warm weather can also bring more air pollution. Here’s what to know.