Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 77 | 66 | 73 | 78 | 69 | 89 |
| Tmin | 91 | 80 | 86 | 85 | 91 | 97 |
| Duration of sunshine | 78 | 64 | 75 | 77 | 69 | 78 |
| Precipitation | 99 | 96 | 97 | 100 | 96 | 108 |
| Humidity/Visibility | 64 | 56 | 63 | 62 | 64 | 69 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 55 | 92 | 97 | 105 | 96 | 95 |
| Tmin | 77 | 112 | 116 | 120 | 104 | 119 |
| Duration of sunshine | 51 | 92 | 98 | 104 | 94 | 97 |
| Precipitation | 125 | 135 | 121 | 126 | 130 | 128 |
| Humidity/Visibility | 54 | 81 | 85 | 85 | 79 | 87 |
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. |
