Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 597 | 562 | 619 | 596 | 609 | 599 |
| Tmin | 596 | 560 | 617 | 597 | 608 | 599 |
| Duration of sunshine | 402 | 378 | 375 | 323 | 393 | 326 |
| Precipitation | 202 | 196 | 231 | 228 | 244 | 233 |
| Humidity/Visibility | 180 | 160 | 173 | 166 | 170 | 165 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 611 | 620 | 622 | 639 | 615 | 651 |
| Tmin | 613 | 620 | 622 | 639 | 614 | 648 |
| Duration of sunshine | 386 | 418 | 398 | 390 | 395 | 421 |
| Precipitation | 217 | 222 | 245 | 240 | 209 | 250 |
| Humidity/Visibility | 173 | 177 | 198 | 203 | 207 | 207 |
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. |
