Portsmouth, NH Weather & Growing Conditions
Today
65°F
Sunny
Sunny, with a high near 65. East wind 5 to 10 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 65°F | Sunny | 5 to 10 mph E | 0% |
| Tonight | 47°F | Mostly Clear | 0 to 5 mph SW | 0% |
| Sunday | 62°F | Mostly Cloudy then Rain | 0 to 10 mph S | 87% |
| Sunday Night | 49°F | Rain | 5 to 10 mph NE | 86% |
| Monday | 66°F | Mostly Sunny | 5 to 10 mph NE | 7% |
| Monday Night | 47°F | Mostly Cloudy | 5 to 10 mph NE | 0% |
| Tuesday | 62°F | Partly Sunny | 10 mph NE | 1% |
| Tuesday Night | 47°F | Mostly Cloudy | 5 to 10 mph NE | 1% |
| Wednesday | 63°F | Mostly Sunny | 10 to 15 mph NE | 1% |
| Wednesday Night | 46°F | Mostly Cloudy then Slight Chance Rain Showers | 5 to 15 mph NE | 15% |
| Thursday | 62°F | Chance Rain Showers | 10 to 20 mph NE | 30% |
| Thursday Night | 47°F | Chance Rain Showers | 15 mph NE | 33% |
| Friday | 63°F | Chance Rain Showers | 15 to 20 mph N | 33% |
| Friday Night | 48°F | Chance Rain Showers | 15 mph NE | 33% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Portsmouth, NH
Last spring frost
May 4
First fall frost
Oct 8
Growing season
157 days
Hardiness zone
6a
Explore more for Portsmouth, NH: full frost dates · planting calendar · New Hampshire frost dates
Climate data from the nearest NOAA station, Greenland, Nh (3.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.