Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1115 | 1008 | 1116 | 1078 | 1115 | 1080 |
| Tmin | 1116 | 1007 | 1115 | 1078 | 1114 | 1078 |
| Duration of sunshine | 372 | 336 | 402 | 418 | 463 | 448 |
| Precipitation | 186 | 169 | 186 | 181 | 186 | 180 |
| Humidity/Visibility | 185 | 168 | 185 | 178 | 184 | 178 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1111 | 1115 | 1109 | 1138 | 1105 | 1147 |
| Tmin | 1110 | 1118 | 1108 | 1142 | 1108 | 1146 |
| Duration of sunshine | 396 | 405 | 419 | 426 | 387 | 402 |
| Precipitation | 184 | 190 | 210 | 215 | 210 | 217 |
| Humidity/Visibility | 180 | 185 | 207 | 210 | 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. |
