Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 701 | 631 | 705 | 679 | 701 | 678 |
| Tmin | 705 | 637 | 704 | 680 | 705 | 683 |
| Duration of sunshine | 70 | 68 | 90 | 83 | 110 | 91 |
| Precipitation | 686 | 615 | 680 | 657 | 684 | 660 |
| Humidity/Visibility | 83 | 75 | 85 | 79 | 84 | 82 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 704 | 732 | 704 | 720 | 676 | 705 |
| Tmin | 707 | 733 | 710 | 715 | 686 | 704 |
| Duration of sunshine | 100 | 130 | 116 | 93 | 67 | 50 |
| Precipitation | 684 | 715 | 692 | 705 | 659 | 684 |
| Humidity/Visibility | 90 | 105 | 102 | 97 | 82 | 87 |
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. |
