With partly cloudy skies, expect highs in the upper 80s to low 90s (except mid 80s in higher elevations of southern NH). Heat index values could reach the mid 90s in spots with very humid conditions (dewpoints in the upper 60s to low 70s). Winds will be southwest at 5-15 mph, with gusts of 25-40 mph possible.
An isolated shower or thunderstorm is not out of the question through the afternoon, and then some showers and thunderstorms are likely from late evening and into the overnight hours. A storm or two could be strong to severe with damaging winds possible, along with torrential rainfall, mainly in western areas, but the better chance for severe weather is well to the west. The storms will weaken as they move east, which will likely be after midnight, but the line may hold together to bring briefly gusty winds and heavy rains in eastern areas. Later tomorrow morning a cold front moves through the area, bringing a much less humid airmass to the region.
Have a great day!