Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 737 | 669 | 741 | 718 | 740 | 719 |
| Tmin | 739 | 667 | 742 | 716 | 741 | 716 |
| Duration of sunshine | 295 | 240 | 268 | 257 | 232 | 260 |
| Precipitation | 188 | 172 | 186 | 187 | 186 | 180 |
| Humidity/Visibility | 178 | 165 | 183 | 177 | 183 | 177 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 742 | 741 | 748 | 766 | 741 | 773 |
| Tmin | 742 | 742 | 743 | 765 | 746 | 773 |
| Duration of sunshine | 266 | 292 | 284 | 317 | 351 | 368 |
| Precipitation | 188 | 192 | 212 | 217 | 212 | 217 |
| Humidity/Visibility | 183 | 183 | 205 | 208 | 204 | 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. |
