Yamanouchi Weather in September
September in Yamanouchi averages 24°C (75°F) during the day and 15°C (59°F) at night. September is part of the rainy season, with around 192 mm (7.6 in) of rainfall and frequent showers.
Rainfall in Yamanouchi in September
Yamanouchi is in the rainy season in September, with rain on around 21 days and an average of 192 mm (7.6 in). With rain on many days and solid totals, showers are frequent and often moderately heavy. Waterproof gear is a sensible idea.
Temperature in Yamanouchi in September
September in Yamanouchi brings high temperatures, with highs of 24°C (75°F) and nights around 15°C (59°F). September is part of the summer season. Conditions stay fairly consistent through the month, making it easier to plan what to wear. Nights cool down to 15°C (59°F), so a light jacket or extra layer is useful once the sun goes down. On the plus side, the cooler nights make for comfortable sleeping conditions.
Sunshine in Yamanouchi in September
The month brings about 142 hours of sunlight, offering a comfortable mix of sun and rainy moments.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 Yamanouchi's climate page.
Yamanouchi Temperature in September
Min Temperature
15°C (59°F)
Max Temperature
24°C (75°F)
Chance of Rain
68%
Precipitation
192 mm (7.6 in)
Rainy days
21 days
Humidity
74% *
Sunshine
142 hours *
Percentage Sunshine
*
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Yamanouchi typically drop from around 28°C (82°F) at the start of September to approximately 22°C (72°F) by the end. Nights are pleasant, with lows typically ranging from 14°C (57°F) to 21°C (70°F).
Average temperatures in September
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 September
Historical weather for Yamanouchi in September
Browse day-by-day weather records for Yamanouchi spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Yamanouchi historical weather extremes in September
Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Yamanouchi.
- On September 1, 2025, temperatures climbed to 35°C (95°F), marking the warmest September day on record.
- On September 21, 2003, Yamanouchi saw its coldest September day with temperatures maxing out at 15°C (59°F).
- The coldest night in September in Yamanouchi was on September 23, 2001, with a minimum of 8°C (46°F).
Best Places in Japan in September
Find out more about the weather in Japan and which places have the best travel conditions in this month. See all of Japan in September →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Yamanouchi in September
Comfortable temperatures call for an easy wardrobe in September. Pack summer basics like t-shirts and shorts, but include a light jacket for cooler moments. A pair of comfortable walking shoes is essential. It's going to pour! Pack a good poncho and prepare for very wet conditions. Bring sunglasses since you'll have some sunny periods throughout the monthWhat To Do in Yamanouchi in September
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 Yamanouchi's climate page.
Temperature Rainfall Sunshine Humidity
See the full Yamanouchi climate overview or explore weather in Japan.
