Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 938 | 867 | 951 | 925 | 958 | 927 |
| Tmin | 940 | 866 | 954 | 928 | 959 | 925 |
| Duration of sunshine | 368 | 358 | 399 | 358 | 401 | 325 |
| Precipitation | 186 | 168 | 188 | 181 | 186 | 180 |
| Humidity/Visibility | 183 | 167 | 184 | 178 | 184 | 177 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 958 | 958 | 956 | 981 | 954 | 991 |
| Tmin | 957 | 959 | 957 | 984 | 952 | 989 |
| Duration of sunshine | 367 | 431 | 447 | 427 | 383 | 367 |
| Precipitation | 186 | 192 | 212 | 215 | 212 | 219 |
| Humidity/Visibility | 182 | 183 | 206 | 209 | 205 | 212 |
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. |
