Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 701 | 618 | 690 | 694 | 721 | 698 |
| Tmin | 704 | 622 | 692 | 697 | 730 | 700 |
| Duration of sunshine | 59 | 48 | 55 | 56 | 57 | 52 |
| Precipitation | 500 | 451 | 495 | 502 | 528 | 509 |
| Humidity/Visibility | 70 | 64 | 70 | 80 | 94 | 89 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 714 | 711 | 697 | 715 | 682 | 707 |
| Tmin | 716 | 715 | 701 | 722 | 682 | 706 |
| Duration of sunshine | 51 | 50 | 51 | 52 | 81 | 84 |
| Precipitation | 526 | 529 | 514 | 521 | 490 | 107 |
| Humidity/Visibility | 90 | 80 | 86 | 81 | 63 | 68 |
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. |
