Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 697 | 645 | 724 | 678 | 708 | 697 |
| Tmin | 719 | 663 | 736 | 683 | 719 | 714 |
| Duration of sunshine | 93 | 29 | 62 | 90 | 124 | 120 |
| Precipitation | 132 | 118 | 126 | 121 | 130 | 126 |
| Humidity/Visibility | 88 | 97 | 110 | 79 | 90 | 103 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 720 | 701 | 676 | 712 | 645 | 684 |
| Tmin | 738 | 719 | 703 | 732 | 663 | 689 |
| Duration of sunshine | 124 | 93 | 120 | 155 | 60 | 31 |
| Precipitation | 131 | 135 | 135 | 125 | 125 | 132 |
| Humidity/Visibility | 104 | 91 | 91 | 102 | 54 | 71 |
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. |
