Frequently the average temperatures in Heidelberg during the month of September is 15, with highs being around 21 with lows about 12 degrees. For more context we have put some more information below:
| Month | Degrees Celsius |
|---|---|
| Temperature | 15 |
| High Temperature | 21 |
| Low Temperature | 12 |
Useful Links: Heidelberg Weather: Average Weather & Yearly Climate