Karuizawa Weather in October
October in Karuizawa averages 18°C (64°F) during the day and 9°C (48°F) at night. October is part of the rainy season, with around 178 mm (7 in) of rainfall and frequent showers.
Rainfall in Karuizawa in October
Karuizawa is in the rainy season in October, with rain on around 15 days and an average of 178 mm (7 in). Rainy season showers tend to be fairly substantial. A good rain jacket or umbrella is worth having with you most days.
Temperature in Karuizawa in October
In October, Karuizawa sees moderate temperatures, with highs of 18°C (64°F). Nights drop to around 9°C (48°F). The difference between afternoon and evening temperatures is usually noticeable. Nights drop to 9°C (48°F). Cold nights like these are actually great for sleeping well, as long as you have a warm enough duvet.
Sunshine in Karuizawa in October
You can expect a moderate amount of sunlight, with approximately 155 hours. Even though this month is part of the wet season, you can still see the sun occasionally.If you prefer dry days with pleasant temperatures, May 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.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Japan, check out our Karuizawa's climate page.
Karuizawa Temperature in October
Min Temperature
9°C (48°F)
Max Temperature
18°C (64°F)
Chance of Rain
49%
Precipitation
178 mm (7 in)
Rainy days
15 days
Humidity
75% *
Sunshine
155 hours *
Percentage Sunshine
*
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Karuizawa typically drop from around 20°C (68°F) at the start of October to approximately 15°C (59°F) by the end. Nights are cool, with lows typically ranging from 5°C (41°F) to 12°C (54°F).
Average temperatures in October
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in October
Historical weather for Karuizawa in October
Browse day-by-day weather records for Karuizawa spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Karuizawa historical weather extremes in October
Based on 49 years of weather observations in Karuizawa between 1976 and 2025, these are the recorded extremes.
- Karuizawa recorded its highest October temperature of 29°C (84°F) on October 1, 1979.
- The coldest October day was on October 28, 2010, with a maximum of 5°C (41°F).
- The lowest overnight temperature recorded in October was -2°C (28°F) (October 27, 2022).
Best Places in Japan in October
Find out more about the weather in Japan and which places have the best travel conditions in this month. See all of Japan in October →
perfect weather
pleasant
tolerable
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What to Wear in Karuizawa in October
For Karuizawa in October, you'll want flexible clothing. It's wise to pack cotton shirts, comfortable shorts, and a pair of jeans for cooler evenings. A light sweater or jacket is useful for air-conditioned spaces (like buses) or unexpected cool moments. Also bring a poncho, it will rain a lot! Waterproof everything you can. Bring sunglasses since you'll have some sunny periods throughout the monthWhat To Do in Karuizawa in October
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 Japan, check out our Karuizawa's climate page.
Temperature Rainfall Sunshine Humidity
See the full Karuizawa climate overview or explore weather in Japan.
