Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 700 | 632 | 704 | 670 | 676 | 656 |
| Tmin | 701 | 636 | 705 | 668 | 678 | 659 |
| Duration of sunshine | 62 | 67 | 98 | 82 | 87 | 84 |
| Precipitation | 682 | 616 | 682 | 661 | 685 | 660 |
| Humidity/Visibility | 112 | 101 | 114 | 105 | 112 | 108 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 684 | 707 | 684 | 699 | 678 | 704 |
| Tmin | 684 | 708 | 682 | 698 | 684 | 703 |
| Duration of sunshine | 91 | 119 | 99 | 85 | 57 | 47 |
| Precipitation | 686 | 715 | 692 | 705 | 659 | 684 |
| Humidity/Visibility | 117 | 139 | 136 | 129 | 109 | 116 |
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. |
