Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 571 | 523 | 576 | 558 | 586 | 577 |
| Tmin | 570 | 525 | 577 | 566 | 592 | 585 |
| Duration of sunshine | 39 | 52 | 50 | 53 | 62 | 72 |
| Precipitation | 75 | 66 | 69 | 67 | 87 | 105 |
| Humidity/Visibility | 38 | 41 | 40 | 42 | 49 | 58 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 606 | 612 | 581 | 592 | 575 | 593 |
| Tmin | 608 | 602 | 583 | 597 | 570 | 613 |
| Duration of sunshine | 79 | 73 | 72 | 68 | 59 | 87 |
| Precipitation | 99 | 109 | 108 | 106 | 118 | 102 |
| Humidity/Visibility | 69 | 66 | 58 | 53 | 51 | 63 |
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. |
