Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 677 | 602 | 674 | 657 | 680 | 655 |
| Tmin | 742 | 668 | 742 | 713 | 743 | 717 |
| Duration of sunshine | 184 | 163 | 184 | 157 | 176 | 168 |
| Precipitation | 622 | 562 | 620 | 609 | 620 | 600 |
| Humidity/Visibility | 150 | 131 | 148 | 144 | 153 | 146 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 700 | 689 | 672 | 722 | 686 | 713 |
| Tmin | 742 | 743 | 743 | 766 | 743 | 771 |
| Duration of sunshine | 176 | 165 | 192 | 198 | 196 | 213 |
| Precipitation | 624 | 626 | 632 | 649 | 634 | 217 |
| Humidity/Visibility | 160 | 157 | 168 | 185 | 174 | 181 |
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. |
