Portsmouth — Water Temperature in August
Water Temperature Range
16°C
minimum
19°C
average
22°C
maximum
Water Temperature Chart for Month
The chart shows the average daily water temperature for each day of the month based on historical data.
Table of Water Temperatures by Day of the Month for Previous Years
| Day | 2025 | 2024 | 2023 | 2022 |
|---|---|---|---|---|
| AUG 1 | 18°C | 18°C | 17°C | 19°C |
| AUG 2 | 18°C | 18°C | 17°C | 18°C |
| AUG 3 | 19°C | 19°C | 18°C | 19°C |
| AUG 4 | 19°C | 19°C | 18°C | 19°C |
| AUG 5 | 20°C | 20°C | 19°C | 21°C |
| AUG 6 | 19°C | 19°C | 18°C | 19°C |
| AUG 7 | 20°C | 20°C | 18°C | 21°C |
| AUG 8 | 18°C | 18°C | 18°C | 18°C |
| AUG 9 | 20°C | 20°C | 19°C | 21°C |
| AUG 10 | 19°C | 19°C | 19°C | 19°C |
| AUG 11 | 19°C | 19°C | 20°C | 18°C |
| AUG 12 | 20°C | 20°C | 20°C | 20°C |
| AUG 13 | 20°C | 20°C | 20°C | 20°C |
| AUG 14 | 21°C | 21°C | 20°C | 22°C |
| AUG 15 | 21°C | 21°C | 21°C | 20°C |
| AUG 16 | 22°C | 22°C | 21°C | 22°C |
| AUG 17 | 20°C | 20°C | 21°C | 18°C |
| AUG 18 | 21°C | 21°C | 20°C | 21°C |
| AUG 19 | 19°C | 19°C | 20°C | 18°C |
| AUG 20 | 20°C | 20°C | 19°C | 21°C |
| AUG 21 | 19°C | 19°C | 19°C | 19°C |
| AUG 22 | 20°C | 20°C | 21°C | 19°C |
| AUG 23 | 20°C | 20°C | 19°C | 20°C |
| AUG 24 | 21°C | 21°C | 19°C | 22°C |
| AUG 25 | 20°C | 20°C | 19°C | 20°C |
| AUG 26 | 21°C | 21°C | 20°C | 21°C |
| AUG 27 | 19°C | 19°C | 20°C | 18°C |
| AUG 28 | 21°C | 21°C | 20°C | 22°C |
| AUG 29 | 20°C | 20°C | 20°C | 20°C |
| AUG 30 | 20°C | 20°C | 20°C | 20°C |
| AUG 31 | 20°C | 20°C | 19°C | 21°C |
August: Climate and Swimming Opportunities
Average Night Air Temperature
17°C
Average Day Air Temperature
26°C
Precipitation Amount per Month
93 mm
Number of Rainy Days
10
Daylight per Day
14 hrs
Sunshine per Day
9 hrs
Average Wind Speed
13 km/h
Average Humidity
72%
With such a ratio between the average monthly temperatures of water and air, the swim feels brisk and very refreshing. The air is warm enough to make the cool water easy to handle, especially for short swims.