Evapotranspiration Calculations
Perth Airport - December 2025 daily calculations
| Date | Evapotrans- piration (mm) 0000- 2400 | Rain (mm) 0900- 0900 | Pan Evaporation (mm) 0900- 0900 | Max Temp | Min Temp | Max Rel Hum (%) | Min Rel Hum (%) | Average 10m Wind Speed (m/sec) | Solar Radiation (MJ/sq m) |
|---|---|---|---|---|---|---|---|---|---|
| 01/12/2025 | 11.4 | 0.0 | 10.0 | 39.7 | 14.8 | 74 | 5 | 5.08 | 31.29 |
| 02/12/2025 | 8.6 | 0.0 | 11.4 | 34.9 | 14.1 | 80 | 18 | 4.27 | 28.45 |
| 03/12/2025 | 7.6 | 0.0 | 7.4 | 28.7 | 16.2 | 84 | 36 | 6.27 | 31.39 |
| 04/12/2025 | 7.1 | 0.0 | 8.2 | 27.9 | 12.7 | 83 | 38 | 5.75 | 31.31 |
| 05/12/2025 | 7.0 | 0.0 | 8.8 | 26.1 | 14.3 | 70 | 36 | 6.43 | 27.80 |
| 06/12/2025 | 8.0 | 0.0 | 7.6 | 29.7 | 15.0 | 73 | 31 | 5.58 | 31.55 |
| 07/12/2025 | 7.4 | 0.0 | 7.6 | 29.4 | 12.7 | 90 | 30 | 4.78 | 31.64 |
| 08/12/2025 | 7.6 | 0.0 | 8.6 | 30.6 | 14.6 | 91 | 38 | 5.67 | 31.60 |
| 09/12/2025 | 7.8 | 0.0 | 9.2 | 30.8 | 16.1 | 78 | 36 | 4.97 | 31.63 |
| 10/12/2025 | 10.7 | 0.0 | 9.6 | 36.1 | 16.6 | 65 | 19 | 6.26 | 31.68 |
| 11/12/2025 | 9.9 | 0.0 | 9.2 | 36.4 | 18.8 | 72 | 26 | 5.70 | 31.60 |
| 12/12/2025 | 10.2 | 0.0 | 11.2 | 36.7 | 19.4 | 100 | 19 | 6.30 | 31.65 |
| 13/12/2025 | 12.0 | 0.2 | 11.8 | 37.4 | 17.7 | 64 | 16 | 7.28 | 31.71 |
| 14/12/2025 | 12.3 | 0.0 | 10.6 | 41.0 | 21.9 | 94 | 17 | 9.60 | 20.15 |
| 15/12/2025 | 8.8 | 16.8 | 8.6 | 35.1 | 21.5 | 84 | 32 | 4.87 | 31.82 |
| 16/12/2025 | 7.4 | 0.0 | 7.4 | 33.2 | 20.1 | 94 | 41 | 4.29 | 30.11 |
| 17/12/2025 | 7.2 | 0.0 | 9.6 | 27.0 | 20.7 | 79 | 39 | 6.73 | 28.46 |
| 18/12/2025 | 8.8 | 0.0 | 9.0 | 31.9 | 15.8 | 68 | 23 | 5.13 | 31.73 |
| Totals: | 159.8 | 17.0 | 165.8 |
