Number of days available for climatic review
| Paramètre | jan | fev | mar | avr | mai | juin |
| Tmax | 154 | 137 | 154 | 149 | 154 | 150 |
| Tmin | 155 | 140 | 155 | 148 | 155 | 150 |
| Durée d’insolation | 93 | 84 | 93 | 90 | 93 | 90 |
| Précipitation | 153 | 140 | 155 | 151 | 155 | 150 |
| Humidité/Visibilité | 154 | 139 | 154 | 149 | 154 | 149 |
| Paramètre | juillet | août | sep | oct | nov | déc |
| Tmax | 151 | 150 | 150 | 146 | 148 | 156 |
| Tmin | 152 | 154 | 149 | 146 | 147 | 155 |
| Durée d’insolation | 124 | 124 | 120 | 124 | 120 | 93 |
| Précipitation | 155 | 157 | 152 | 155 | 150 | 155 |
| Humidité/Visibilité | 153 | 151 | 148 | 148 | 148 | 154 |
Climate data is usually derived from meteorological data of a certain number of years. The actual number of recorded years may vary from only a couple to 50 years or more. The quality of climate data depends on the number of available recorded years. Fewer years means less reliable data. The standart-period for reliable climate data is 30 years. For example, the mean monthly temperature for, let's say January, would ideally calculated from a total number of 930 recorded January-days. However, the usual number of recorded days is much smaller. The table above shows the actual number of recorded days for every parameter measured. |
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