September · Indonesia
Best time to visit Lake Toba in September Weather, crowds & prices
Weather in Lake Toba in September
Average temperature 20°C, 316 mm of rain, about 16 days with 6+ hours of sunshine and 90% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
September score
6.0/10
Ranked #10 of 12 months
- Avg temp
- 20°C
- Rainfall
- 316 mm
- Humidity
- 90%
- Days with 6h+ sun
- 16
- Crowd Density
- Quiet / Uncrowded
- Average Expenses
- $ · Budget Friendly ($)
September in Lake Toba scores 6.0/10 for nature and wildlife travel - ranked #10 of 12. Expect around 20°C, 316 mm of rain, and roughly 16 days with 6+ hours of sunshine this month.
Lake Toba fills a vast volcanic caldera on Sumatra-Batak villages on Samosir Island and misty lakeside viewpoints. Best window: the drier months outside peak monsoon.
September in Lake Toba: mixed conditions, plan around the weather
September averages 20°C (68°F) — warm for the outdoors: start trails early, use shaded routes at midday, and carry more water than you think you need.
316 mm of rain puts this in monsoon territory — about 16 days with 6+ hours of sunshine across the whole month, and multi-day washouts are normal.
It scores 6/10 here, 10th of 12 months, against 6.8/10 in the destination's best month.
Pack light clothing, a hat and real sun protection, a proper rain shell rather than an umbrella, footwear you can get muddy.
Plan for low-season pricing, with crowds are light for this destination.
Frequently asked
- What is the weather like in Lake Toba in September?
- In September, Lake Toba averages 20°C, 316 mm of rain, and about 16 days with 6+ hours of sunshine. Its climate-comfort score is 6.0/10.
- Is September a good time to visit Lake Toba?
- September earns a 6.0/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Lake Toba in September?
- Expect about 316 mm of rain in September. Average humidity is 90% and there are about 16 days with 6+ hours of sunshine.
Curated in Lake Toba
Tickets & experiences
Things to do in Lake Toba
Lake Toba, Indonesia. Live activities and tours from GetYourGuide, matched to this destination.