Meridian boasts a year-around average temperature of 9.9°C, peaking at 16.9°C in July, August, its warmest month, and dipping to an average low of 3.4°C in December, the coolest. Rainfall averages at 75.8mm annually, with November seeing the heaviest showers and July being the driest month.
Month | Temperature (Celcius) | Rainfall (mm) |
| January | 4.0 | 118.6 |
| February | 4.9 | 76.7 |
| March | 6.8 | 81.8 |
| April | 9.1 | 68.3 |
| May | 12.1 | 63.0 |
| June | 14.7 | 47.2 |
| July | 16.9 | 30.0 |
| August | 16.9 | 31.2 |
| September | 14.0 | 45.2 |
| October | 9.9 | 93.5 |
| November | 6.2 | 147.3 |
| December | 3.4 | 107.2 |