Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 117 | 87 | 96 | 109 | 120 | 116 |
| Tmin | 118 | 91 | 93 | 108 | 119 | 119 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 122 | 97 | 121 | 140 | 153 | 156 |
| Humidity/Visibility | 115 | 90 | 110 | 122 | 141 | 138 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 123 | 120 | 118 | 110 | 117 | 123 |
| Tmin | 121 | 122 | 117 | 110 | 113 | 121 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 145 | 150 | 149 | 138 | 121 | 125 |
| Humidity/Visibility | 141 | 140 | 140 | 129 | 117 | 123 |
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. |
