Alton, NH Weather & Growing Conditions
Today
72°F
Mostly Sunny
Mostly sunny. High near 72, with temperatures falling to around 66 in the afternoon. Southwest wind around 5 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 72°F | Mostly Sunny | 5 mph SW | 3% |
| Tonight | 52°F | Partly Cloudy | 5 mph SW | 2% |
| Thursday | 68°F | Mostly Cloudy then Light Rain Likely | 5 to 10 mph SW | 57% |
| Thursday Night | 57°F | Chance Light Rain | 5 to 10 mph SW | 26% |
| Friday | 66°F | Light Rain Likely | 0 to 5 mph S | 60% |
| Friday Night | 51°F | Light Rain | 0 to 5 mph NE | 84% |
| Saturday | 59°F | Light Rain Likely | 5 mph NE | 72% |
| Saturday Night | 42°F | Chance Light Rain | 5 to 10 mph N | 40% |
| Sunday | 53°F | Chance Light Rain | 5 to 10 mph NW | 34% |
| Sunday Night | 35°F | Partly Cloudy | 5 mph W | 7% |
| Monday | 50°F | Mostly Sunny | 5 to 15 mph W | 13% |
| Monday Night | 32°F | Partly Cloudy | 5 to 10 mph W | 12% |
| Tuesday | 52°F | Mostly Sunny | 10 to 15 mph W | 9% |
| Tuesday Night | 32°F | Partly Cloudy | 5 to 10 mph W | 8% |
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 (14.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.