Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 87 | 82 | 119 | 144 | 140 | 142 |
| Tmin | 111 | 100 | 126 | 135 | 132 | 136 |
| Duration of sunshine | 101 | 89 | 118 | 124 | 122 | 128 |
| Precipitation | 152 | 139 | 178 | 174 | 177 | 173 |
| Humidity/Visibility | 69 | 60 | 85 | 91 | 92 | 90 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 138 | 141 | 140 | 125 | 101 | 91 |
| Tmin | 146 | 149 | 150 | 120 | 139 | 144 |
| Duration of sunshine | 113 | 117 | 124 | 109 | 135 | 137 |
| Precipitation | 185 | 188 | 201 | 179 | 200 | 182 |
| Humidity/Visibility | 92 | 95 | 98 | 82 | 93 | 83 |
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. |
