Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 616 | 557 | 621 | 600 | 620 | 592 |
| Tmin | 626 | 575 | 621 | 601 | 630 | 600 |
| Duration of sunshine | 129 | 155 | 121 | 86 | 158 | 113 |
| Precipitation | 567 | 506 | 569 | 555 | 574 | 546 |
| Humidity/Visibility | 88 | 87 | 92 | 86 | 92 | 78 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 619 | 620 | 601 | 604 | 597 | 619 |
| Tmin | 620 | 628 | 604 | 606 | 593 | 627 |
| Duration of sunshine | 120 | 197 | 89 | 139 | 113 | 128 |
| Precipitation | 563 | 585 | 552 | 565 | 555 | 579 |
| Humidity/Visibility | 92 | 89 | 81 | 69 | 78 | 85 |
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. |
