Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 110 | 84 | 112 | 120 | 129 | 127 |
| Tmin | 111 | 100 | 112 | 126 | 136 | 134 |
| Duration of sunshine | 95 | 85 | 99 | 117 | 132 | 122 |
| Precipitation | 128 | 112 | 126 | 142 | 155 | 151 |
| Humidity/Visibility | 111 | 96 | 110 | 121 | 136 | 129 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 124 | 125 | 130 | 124 | 110 | 118 |
| Tmin | 129 | 125 | 134 | 126 | 100 | 119 |
| Duration of sunshine | 118 | 119 | 127 | 114 | 80 | 109 |
| Precipitation | 153 | 165 | 161 | 151 | 126 | 140 |
| Humidity/Visibility | 131 | 126 | 134 | 128 | 104 | 118 |
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. |
