Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 598 | 552 | 612 | 590 | 611 | 591 |
| Tmin | 549 | 499 | 576 | 559 | 579 | 561 |
| Duration of sunshine | 266 | 213 | 235 | 268 | 262 | 253 |
| Precipitation | 187 | 167 | 186 | 173 | 186 | 179 |
| Humidity/Visibility | 122 | 112 | 139 | 131 | 144 | 139 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 609 | 612 | 617 | 627 | 620 | 598 |
| Tmin | 575 | 579 | 592 | 595 | 590 | 585 |
| Duration of sunshine | 323 | 324 | 346 | 329 | 233 | 303 |
| Precipitation | 184 | 189 | 206 | 206 | 206 | 189 |
| Humidity/Visibility | 141 | 150 | 161 | 151 | 154 | 131 |
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. |
