Yosemite National Park is definitely worth a visit
Vast forests, blue lakes, towering sequoias, and majestic waterfalls hint at the beauty of Yosemite National Park—a true natural masterpiece.
Portsmouth in October averages 16°C (61°F) during the day and 6°C (43°F) at night. Keep in mind that quite a bit of rainfall is expected this month.
If you prefer enjoying temperate temperatures and rain-free days, September typically offers the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.
Pick a month to see the average temperature, rainfall and sunshine in Portsmouth - and find the best time to visit.
49-year average (1976-2025)
Based on our historical records, temperatures in Portsmouth typically drop from around 18°C (64°F) at the start of October to approximately 13°C (55°F) by the end. Nights are cold, with lows typically ranging from 2°C (36°F) to 8°C (46°F).
49-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
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.
Based on 28 years of weather observations in Portsmouth between 1997 and 2025, these are the recorded extremes.
Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in October →
Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).
The weather can be unpredictable in October, so pack clothes you can easily mix and match. You could bring jeans, other long pants, and a few t-shirts. A light jacket or light sweater will be pleasant for the cooler moments. High rain levels are expected, so pack waterproof gear and an umbrella or poncho. It won't hurt to bring your sunglasses along, as you'll see some sunny periods.
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Temperature Rainfall Sunshine Humidity
See the full Portsmouth climate overview or explore weather in the United States of America.
Where to go in October - average daytime high across popular destinations.
Need travel inspiration? Check out our bucket list articles and be inspired.
Yosemite National Park is definitely worth a visit
Vast forests, blue lakes, towering sequoias, and majestic waterfalls hint at the beauty of Yosemite National Park—a true natural masterpiece.
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