Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 742 | 676 | 744 | 719 | 743 | 719 |
| Tmin | 744 | 675 | 744 | 719 | 743 | 718 |
| Duration of sunshine | 837 | 758 | 834 | 809 | 834 | 808 |
| Precipitation | 188 | 168 | 187 | 181 | 186 | 180 |
| Humidity/Visibility | 185 | 167 | 185 | 179 | 185 | 179 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 743 | 740 | 718 | 735 | 715 | 745 |
| Tmin | 742 | 744 | 719 | 735 | 717 | 744 |
| Duration of sunshine | 804 | 840 | 898 | 921 | 897 | 898 |
| Precipitation | 188 | 190 | 210 | 215 | 210 | 217 |
| Humidity/Visibility | 184 | 184 | 207 | 209 | 207 | 215 |
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. |
