Harman US

Alton, NH Weather & Growing Conditions

Today
69°F
Mostly Sunny
Mostly sunny. High near 69, with temperatures falling to around 63 in the afternoon. Southwest wind 5 to 10 mph.

7-day forecast

WhenTempForecastWindPrecip
Today 69°F Mostly Sunny 5 to 10 mph SW 3%
Tonight 52°F Partly Cloudy 10 mph SW 2%
Thursday 64°F Mostly Cloudy then Light Rain Likely 10 to 15 mph SW 60%
Thursday Night 57°F Chance Light Rain 5 to 15 mph SW 31%
Friday 63°F Chance Light Rain 0 to 5 mph SW 52%
Friday Night 52°F Light Rain 0 to 10 mph NE 82%
Saturday 56°F Light Rain Likely 5 to 10 mph NE 69%
Saturday Night 44°F Chance Light Rain 5 to 10 mph N 41%
Sunday 50°F Chance Light Rain 5 to 10 mph NW 34%
Sunday Night 39°F Partly Cloudy 5 mph W 8%
Monday 48°F Mostly Sunny 10 to 15 mph W 14%
Monday Night 36°F Partly Cloudy 10 mph W 13%
Tuesday 49°F Mostly Sunny 10 to 15 mph W 9%
Tuesday Night 36°F Partly Cloudy 10 mph W 9%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Alton, NH

Last spring frost
Apr 30
First fall frost
Oct 18
Growing season
170 days
Hardiness zone
5b

Explore more for Alton, NH: full frost dates · planting calendar · New Hampshire frost dates

Climate data from the nearest NOAA station, Lakeport 2, Nh (8.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.