Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 717 | 657 | 729 | 701 | 715 | 697 |
| Tmin | 735 | 669 | 739 | 711 | 734 | 713 |
| Duration of sunshine | 31 | 0 | 31 | 30 | 93 | 60 |
| Precipitation | 131 | 118 | 129 | 129 | 137 | 130 |
| Humidity/Visibility | 109 | 99 | 111 | 106 | 101 | 105 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 718 | 720 | 694 | 714 | 664 | 698 |
| Tmin | 733 | 738 | 712 | 738 | 682 | 739 |
| Duration of sunshine | 93 | 93 | 60 | 155 | 60 | 0 |
| Precipitation | 133 | 134 | 127 | 125 | 124 | 129 |
| Humidity/Visibility | 106 | 108 | 104 | 104 | 75 | 105 |
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. |
