Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 651 | 589 | 651 | 628 | 665 | 660 |
| Tmin | 680 | 616 | 674 | 655 | 689 | 678 |
| Duration of sunshine | 93 | 29 | 62 | 60 | 93 | 60 |
| Precipitation | 93 | 85 | 92 | 92 | 107 | 122 |
| Humidity/Visibility | 75 | 69 | 74 | 73 | 87 | 99 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 681 | 677 | 660 | 676 | 644 | 682 |
| Tmin | 702 | 705 | 685 | 700 | 671 | 685 |
| Duration of sunshine | 31 | 31 | 30 | 31 | 90 | 124 |
| Precipitation | 127 | 126 | 120 | 124 | 123 | 99 |
| Humidity/Visibility | 103 | 105 | 101 | 97 | 100 | 93 |
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. |
