Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 806 | 727 | 802 | 778 | 804 | 791 |
| Tmin | 806 | 729 | 804 | 780 | 806 | 792 |
| Duration of sunshine | 248 | 168 | 186 | 240 | 248 | 240 |
| Precipitation | 62 | 60 | 64 | 61 | 64 | 74 |
| Humidity/Visibility | 61 | 55 | 60 | 59 | 61 | 71 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 835 | 834 | 809 | 833 | 806 | 836 |
| Tmin | 832 | 835 | 808 | 831 | 807 | 836 |
| Duration of sunshine | 217 | 279 | 270 | 248 | 210 | 279 |
| Precipitation | 96 | 95 | 94 | 91 | 90 | 95 |
| Humidity/Visibility | 92 | 90 | 87 | 86 | 87 | 92 |
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. |
