Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 709 | 638 | 706 | 712 | 732 | 717 |
| Tmin | 709 | 638 | 708 | 710 | 734 | 713 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 712 | 645 | 721 | 722 | 751 | 719 |
| Humidity/Visibility | 122 | 109 | 117 | 140 | 146 | 147 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 737 | 734 | 714 | 728 | 709 | 741 |
| Tmin | 738 | 736 | 710 | 730 | 711 | 734 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 745 | 748 | 717 | 739 | 723 | 757 |
| Humidity/Visibility | 150 | 148 | 142 | 142 | 138 | 148 |
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. |
