Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 694 | 626 | 698 | 668 | 693 | 672 |
| Tmin | 686 | 623 | 686 | 667 | 700 | 675 |
| Duration of sunshine | 78 | 64 | 79 | 72 | 82 | 77 |
| Precipitation | 158 | 132 | 148 | 139 | 137 | 136 |
| Humidity/Visibility | 101 | 96 | 106 | 96 | 106 | 104 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 673 | 703 | 695 | 709 | 664 | 691 |
| Tmin | 678 | 689 | 686 | 697 | 655 | 676 |
| Duration of sunshine | 88 | 77 | 79 | 64 | 44 | 39 |
| Precipitation | 124 | 189 | 186 | 170 | 155 | 180 |
| Humidity/Visibility | 87 | 105 | 122 | 117 | 94 | 101 |
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. |
