Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 826 | 746 | 828 | 801 | 832 | 803 |
| Tmin | 688 | 620 | 691 | 675 | 692 | 668 |
| Duration of sunshine | 248 | 254 | 186 | 210 | 279 | 240 |
| Precipitation | 155 | 140 | 154 | 151 | 155 | 150 |
| Humidity/Visibility | 133 | 123 | 131 | 131 | 136 | 131 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 829 | 826 | 800 | 829 | 801 | 803 |
| Tmin | 694 | 694 | 675 | 700 | 688 | 687 |
| Duration of sunshine | 310 | 248 | 300 | 248 | 270 | 310 |
| Precipitation | 157 | 157 | 150 | 153 | 151 | 131 |
| Humidity/Visibility | 133 | 136 | 128 | 128 | 119 | 120 |
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. |
