Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 833 | 754 | 837 | 808 | 832 | 810 |
| Tmin | 836 | 752 | 833 | 808 | 836 | 807 |
| Duration of sunshine | 210 | 214 | 241 | 229 | 234 | 227 |
| Precipitation | 186 | 168 | 187 | 181 | 186 | 180 |
| Humidity/Visibility | 183 | 164 | 183 | 178 | 184 | 178 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 835 | 789 | 769 | 774 | 736 | 745 |
| Tmin | 835 | 788 | 769 | 773 | 735 | 744 |
| Duration of sunshine | 230 | 178 | 187 | 170 | 164 | 152 |
| Precipitation | 188 | 190 | 212 | 215 | 210 | 217 |
| Humidity/Visibility | 183 | 184 | 204 | 210 | 205 | 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. |
