Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 834 | 782 | 867 | 861 | 884 | 867 |
| Tmin | 835 | 782 | 863 | 859 | 885 | 865 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 124 | 117 | 130 | 146 | 155 | 150 |
| Humidity/Visibility | 121 | 110 | 121 | 141 | 153 | 148 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 892 | 889 | 863 | 889 | 864 | 895 |
| Tmin | 892 | 890 | 859 | 889 | 868 | 892 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 158 | 157 | 151 | 153 | 150 | 158 |
| Humidity/Visibility | 150 | 148 | 146 | 148 | 146 | 152 |
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. |
