Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 767 | 695 | 768 | 766 | 795 | 773 |
| Tmin | 771 | 697 | 770 | 764 | 796 | 767 |
| Duration of sunshine | 279 | 254 | 248 | 210 | 248 | 300 |
| Precipitation | 125 | 114 | 125 | 146 | 156 | 153 |
| Humidity/Visibility | 120 | 110 | 121 | 139 | 147 | 145 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 799 | 798 | 777 | 796 | 777 | 803 |
| Tmin | 799 | 797 | 776 | 794 | 774 | 799 |
| Duration of sunshine | 279 | 279 | 240 | 279 | 240 | 186 |
| Precipitation | 156 | 157 | 153 | 156 | 158 | 157 |
| Humidity/Visibility | 151 | 149 | 146 | 145 | 144 | 150 |
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. |
