Portsmouth

What is the climate like in Portsmouth?

The best time to visit Portsmouth is typically August, the year's most comfortable month (6.6/10). Portsmouth is warmest in July, when daily highs average 75°F (24°C), and coolest in January, when lows fall to about 31°F (-1°C). The wettest month is typically December and the driest is June; the year sees roughly 54 in (1360 mm) of precipitation.

• Best time to visitAugust — the year's comfort peak (6.6/10)
• Warmest monthJuly — average high 75°F (24°C)
• Coolest monthJanuary — average low 31°F (-1°C)
• Wettest monthDecember (5.6 in (142 mm))
• Driest monthJune (3.2 in (82 mm))
• Annual precipitation54 in (1360 mm)
• Based on2016-2025 daily ERA5 reanalysis data (10-year normals)
• Records fromNewport State AP, 8 km away (1996-2026)