Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 712 | 642 | 713 | 689 | 710 | 688 |
| Tmin | 712 | 644 | 712 | 684 | 712 | 690 |
| Duration of sunshine | 154 | 138 | 153 | 141 | 151 | 138 |
| Precipitation | 682 | 616 | 682 | 661 | 684 | 662 |
| Humidity/Visibility | 153 | 138 | 153 | 147 | 152 | 146 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 710 | 709 | 690 | 706 | 689 | 711 |
| Tmin | 713 | 713 | 689 | 706 | 687 | 709 |
| Duration of sunshine | 152 | 154 | 149 | 145 | 147 | 150 |
| Precipitation | 684 | 684 | 664 | 682 | 660 | 684 |
| Humidity/Visibility | 152 | 151 | 147 | 148 | 147 | 150 |
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. |
