Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 732 | 672 | 767 | 736 | 759 | 735 |
| Tmin | 702 | 633 | 693 | 669 | 684 | 655 |
| Duration of sunshine | 95 | 79 | 69 | 72 | 78 | 63 |
| Precipitation | 742 | 673 | 744 | 723 | 745 | 719 |
| Humidity/Visibility | 106 | 96 | 107 | 105 | 109 | 101 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 757 | 735 | 735 | 763 | 761 | 757 |
| Tmin | 687 | 674 | 678 | 693 | 681 | 729 |
| Duration of sunshine | 77 | 58 | 63 | 63 | 82 | 126 |
| Precipitation | 744 | 730 | 721 | 760 | 753 | 196 |
| Humidity/Visibility | 103 | 92 | 89 | 100 | 121 | 114 |
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. |
