Portsmouth Weather in August
In Portsmouth, August brings high daytime temperatures around 29°C (84°F), with nights cooling to 26°C (79°F). Expect quite a bit of rainfall this month.
Rainfall in Portsmouth in August
Past climate data indicates that roughly 20 days will see rain, totalling around 117 mm (4.6 in) for the month. Rain falls regularly this month and can be quite heavy when it does. Showers can be substantial, so waterproof gear is a good idea.
Temperature in Portsmouth in August
In August, expect high temperatures in Portsmouth, with highs of 29°C (84°F) and lows of 26°C (79°F) at night. Conditions stay fairly consistent through the month, making it easier to plan what to wear. Nights remain warm at around 26°C (79°F). For a more comfortable sleep, a cold shower before bed and a fan or air conditioning can make a big difference.
Sunshine in Portsmouth in August
With approximately 240 hours of sunshine, the days are filled with clear skies. It makes it a perfect month for being outside.August in Portsmouth has its charm. However, if you're seeking pleasant, dry and sunny weather, our weather planner can help you explore other destinations in the world.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Dominica, check out our Portsmouth's climate page.
Portsmouth Temperature in August
Min Temperature
26°C (79°F)
Max Temperature
29°C (84°F)
Chance of Rain
67%
Precipitation
117 mm (4.6 in)
Rainy days
20 days
Humidity
71% *
Sunshine
240 hours *
Percentage Sunshine
*
Daily Historical Temperatures
49-year average (1976-2025)
Based on our historical records, temperatures in Portsmouth typically stay consistent throughout August, with daily highs averaging around 29°C (84°F). Nights are warm, with lows around 24°C (75°F).
Average temperatures in August
Historical weather for Portsmouth in August
Browse day-by-day weather records for Portsmouth spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Portsmouth historical weather extremes in August
Based on weather observations in Portsmouth between 1987 and 2025, these are the recorded extremes during August.
- The warmest day in August was on August 8, 2023, with a maximum of 36°C (97°F).
- The lowest daytime temperature in August was 26°C (79°F), recorded on August 16, 1988.
- Portsmouth registered its coldest August night on August 12, 2024, with temperatures dropping to 14°C (57°F).
Best Places in Dominica in August
Find out more about the weather in Dominica and which places have the best travel conditions in this month. See all of Dominica in August →
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What to Wear in Portsmouth in August
Warm weather calls for comfortable, breathable clothing in August. Cotton t-shirts, shorts, light dresses, and sandals are perfect. You might still want a light layer for evenings or air-conditioned places (for example buses). High rain levels are expected, so pack waterproof gear and an umbrella or poncho. And with plenty of sunshine hours, don’t forget sunglasses, sunscreen, and maybe a sun hat.What To Do in Portsmouth in August
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Dominica, check out our Portsmouth's climate page.
Temperature Rainfall Sunshine Humidity
See the full Portsmouth climate overview or explore weather in Dominica.
