Typically, the expected weather in Alajuela during September is 21. Average high degrees are usually 28 and typical average low being around 18 celsius. The table below includes more detail:
| Month | Degrees Celsius |
|---|---|
| Temperature | 21 |
| High Temperature | 28 |
| Low Temperature | 18 |
Useful Links: Alajuela Weather: Average Weather & Yearly Climate