Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 86 | 79 | 83 | 115 | 116 | 117 |
| Tmin | 91 | 81 | 87 | 115 | 121 | 116 |
| Duration of sunshine | 56 | 50 | 54 | 58 | 58 | 56 |
| Precipitation | 99 | 93 | 98 | 130 | 130 | 124 |
| Humidity/Visibility | 66 | 61 | 65 | 85 | 88 | 86 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 109 | 120 | 114 | 118 | 109 | 115 |
| Tmin | 117 | 123 | 113 | 117 | 108 | 120 |
| Duration of sunshine | 51 | 60 | 57 | 60 | 57 | 55 |
| Precipitation | 130 | 128 | 129 | 122 | 128 | 130 |
| Humidity/Visibility | 85 | 89 | 84 | 85 | 82 | 88 |
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. |
