Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 650 | 587 | 651 | 630 | 665 | 660 |
| Tmin | 651 | 589 | 649 | 629 | 665 | 658 |
| Duration of sunshine | 93 | 29 | 62 | 90 | 93 | 90 |
| Precipitation | 63 | 58 | 63 | 62 | 76 | 94 |
| Humidity/Visibility | 61 | 55 | 60 | 58 | 75 | 87 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 679 | 674 | 658 | 676 | 629 | 678 |
| Tmin | 677 | 677 | 654 | 677 | 628 | 680 |
| Duration of sunshine | 93 | 0 | 30 | 31 | 120 | 93 |
| Precipitation | 97 | 97 | 93 | 91 | 92 | 93 |
| Humidity/Visibility | 90 | 91 | 85 | 85 | 57 | 90 |
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. |
