Climate almanac
Portsmouth
Rhode Island, United States · 41.60°, -71.25°
What is the weather like in Portsmouth in September?
In September, Portsmouth is typically 70°F (21°C) during the day and 64°F (18°C) at night. The month brings about 4.3 in (109 mm) of precipitation in total.
- Average high70°F (21°C)
- Average low64°F (18°C)
- Precipitation4.3 in (109 mm)
- Clear or mostly clear days10
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)