Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 772 | 683 | 742 | 715 | 740 | 718 |
| Tmin | 774 | 686 | 742 | 717 | 744 | 718 |
| Duration of sunshine | 217 | 145 | 151 | 146 | 149 | 140 |
| Precipitation | 186 | 168 | 186 | 180 | 188 | 182 |
| Humidity/Visibility | 122 | 98 | 90 | 87 | 92 | 89 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 740 | 743 | 746 | 773 | 742 | 770 |
| Tmin | 740 | 743 | 747 | 770 | 746 | 770 |
| Duration of sunshine | 145 | 146 | 165 | 199 | 201 | 213 |
| Precipitation | 186 | 188 | 210 | 213 | 210 | 217 |
| Humidity/Visibility | 91 | 92 | 117 | 122 | 116 | 120 |
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. |
