Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 793 | 715 | 772 | 760 | 791 | 766 |
| Tmin | 768 | 687 | 753 | 742 | 772 | 750 |
| Duration of sunshine | 155 | 141 | 217 | 150 | 124 | 150 |
| Precipitation | 155 | 140 | 150 | 148 | 155 | 150 |
| Humidity/Visibility | 140 | 124 | 134 | 135 | 140 | 133 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 794 | 791 | 771 | 794 | 775 | 764 |
| Tmin | 774 | 771 | 746 | 766 | 743 | 761 |
| Duration of sunshine | 217 | 155 | 210 | 186 | 150 | 124 |
| Precipitation | 157 | 157 | 150 | 153 | 150 | 129 |
| Humidity/Visibility | 141 | 139 | 137 | 138 | 136 | 124 |
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. |
