Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 769 | 732 | 812 | 784 | 815 | 816 |
| Tmin | 772 | 730 | 812 | 789 | 805 | 808 |
| Duration of sunshine | 217 | 169 | 155 | 210 | 217 | 240 |
| Precipitation | 94 | 88 | 98 | 96 | 97 | 104 |
| Humidity/Visibility | 90 | 82 | 88 | 86 | 91 | 100 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 851 | 859 | 827 | 844 | 809 | 834 |
| Tmin | 849 | 856 | 826 | 848 | 810 | 837 |
| Duration of sunshine | 217 | 279 | 210 | 186 | 150 | 155 |
| Precipitation | 130 | 127 | 123 | 120 | 120 | 127 |
| Humidity/Visibility | 119 | 119 | 117 | 115 | 117 | 123 |
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. |
