Generally the typical temperate in Poznan in the course of September is 12. You can expect highs around 18 with low average temperatures being 9 degrees celsius. We have put some more detail below here:
| Month | Degrees Celsius |
|---|---|
| Temperature | 12 |
| High Temperature | 18 |
| Low Temperature | 9 |
Useful Links: Poznan Weather: Average Weather & Yearly Climate