Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 607 | 555 | 596 | 591 | 631 | 602 |
| Tmin | 609 | 547 | 602 | 589 | 634 | 615 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 550 | 492 | 549 | 548 | 563 | 550 |
| Humidity/Visibility | 79 | 75 | 75 | 83 | 102 | 101 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 624 | 622 | 601 | 621 | 610 | 618 |
| Tmin | 622 | 629 | 606 | 634 | 619 | 638 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 570 | 579 | 546 | 570 | 549 | 573 |
| Humidity/Visibility | 99 | 97 | 98 | 100 | 103 | 105 |
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. |
