Evapotranspiration Calculations
Pyrenees (Ben Nevis) - September 2026 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) |
|---|---|---|---|---|---|---|---|---|---|
| 01/09/2026 | 2.5 | 0.0 | 16.4 | 8.6 | 99 | 55 | 5.71 | 14.14 | |
| 02/09/2026 | 1.4 | 3.0 | 10.6 | 4.8 | 99 | 75 | 3.28 | 12.27 | |
| 03/09/2026 | 1.8 | 0.0 | 12.1 | 4.4 | 99 | 59 | 4.15 | 10.99 | |
| 04/09/2026 | 1.4 | 0.2 | 10.2 | 2.9 | 99 | 72 | 5.02 | 10.04 | |
| 05/09/2026 | 1.1 | 18.2 | 10.0 | 6.2 | 99 | 80 | 6.74 | 7.93 | |
| 06/09/2026 | 1.1 | 5.8 | 9.5 | 4.7 | 100 | 85 | 5.94 | 10.35 | |
| 07/09/2026 | 1.9 | 1.0 | 11.3 | 4.5 | 100 | 62 | 6.52 | 14.54 | |
| 08/09/2026 | 3.2 | 0.2 | 12.4 | 3.0 | 99 | 5 | 4.16 | 17.44 | |
| 09/09/2026 | 1.5 | 0.8 | 6.6 | 1.8 | 100 | 65 | 7.06 | 14.13 | |
| 10/09/2026 | 2.8 | 0.0 | 13.1 | 2.4 | 96 | 33 | 4.30 | 17.87 | |
| 11/09/2026 | 4.1 | 0.0 | 17.2 | 4.5 | 78 | 12 | 4.65 | 18.05 | |
| 12/09/2026 | 3.2 | 0.0 | 18.0 | 8.5 | 84 | 52 | 4.91 | 17.82 | |
| 13/09/2026 | 2.8 | 0.0 | 16.7 | 11.5 | 95 | 49 | 7.38 | 9.72 | |
| 14/09/2026 | 2.1 | 0.2 | 15.5 | 8.9 | 99 | 68 | 3.63 | 14.47 | |
| 15/09/2026 | 1.8 | 1.0 | 8.7 | 3.3 | 99 | 61 | 7.78 | 14.60 | |
| Totals: | 32.7 | 30.4 |
