Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 694 | 647 | 717 | 708 | 737 | 726 |
| Tmin | 698 | 648 | 718 | 708 | 737 | 720 |
| Duration of sunshine | 186 | 254 | 248 | 270 | 279 | 270 |
| Precipitation | 93 | 85 | 94 | 108 | 126 | 120 |
| Humidity/Visibility | 92 | 83 | 92 | 104 | 122 | 119 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 746 | 745 | 730 | 768 | 747 | 757 |
| Tmin | 748 | 748 | 723 | 768 | 745 | 762 |
| Duration of sunshine | 279 | 248 | 270 | 310 | 210 | 279 |
| Precipitation | 127 | 127 | 120 | 124 | 120 | 124 |
| Humidity/Visibility | 123 | 121 | 118 | 117 | 117 | 124 |
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. |
