Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 516 | 468 | 522 | 519 | 552 | 531 |
| Tmin | 514 | 463 | 523 | 517 | 551 | 537 |
| Duration of sunshine | 93 | 113 | 124 | 90 | 124 | 120 |
| Precipitation | 95 | 85 | 93 | 108 | 130 | 121 |
| Humidity/Visibility | 60 | 45 | 57 | 69 | 94 | 113 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 550 | 536 | 534 | 551 | 505 | 536 |
| Tmin | 540 | 538 | 533 | 546 | 504 | 542 |
| Duration of sunshine | 124 | 62 | 120 | 62 | 90 | 93 |
| Precipitation | 130 | 127 | 129 | 124 | 122 | 133 |
| Humidity/Visibility | 112 | 108 | 112 | 112 | 100 | 118 |
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. |
