Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 742 | 670 | 742 | 718 | 743 | 718 |
| Tmin | 743 | 670 | 744 | 718 | 744 | 719 |
| Duration of sunshine | 185 | 165 | 186 | 178 | 186 | 178 |
| Precipitation | 653 | 588 | 651 | 631 | 651 | 630 |
| Humidity/Visibility | 183 | 166 | 184 | 178 | 185 | 177 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 732 | 742 | 743 | 765 | 745 | 773 |
| Tmin | 738 | 744 | 748 | 767 | 747 | 771 |
| Duration of sunshine | 180 | 186 | 208 | 209 | 206 | 213 |
| Precipitation | 649 | 657 | 660 | 680 | 659 | 682 |
| Humidity/Visibility | 178 | 184 | 203 | 208 | 206 | 213 |
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. |
