Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 828 | 751 | 832 | 805 | 829 | 807 |
| Tmin | 835 | 751 | 835 | 804 | 835 | 807 |
| Duration of sunshine | 413 | 412 | 443 | 406 | 424 | 439 |
| Precipitation | 186 | 169 | 185 | 181 | 188 | 181 |
| Humidity/Visibility | 178 | 167 | 183 | 170 | 173 | 175 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 830 | 830 | 830 | 854 | 826 | 860 |
| Tmin | 833 | 836 | 830 | 858 | 830 | 863 |
| Duration of sunshine | 449 | 480 | 479 | 463 | 419 | 450 |
| Precipitation | 185 | 192 | 210 | 215 | 212 | 219 |
| Humidity/Visibility | 182 | 183 | 194 | 196 | 195 | 205 |
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. |
