Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 118 | 86 | 91 | 90 | 91 | 90 |
| Tmin | 118 | 91 | 92 | 88 | 90 | 88 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 123 | 95 | 121 | 144 | 157 | 152 |
| Humidity/Visibility | 115 | 91 | 111 | 122 | 142 | 138 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 91 | 90 | 87 | 86 | 88 | 90 |
| Tmin | 93 | 92 | 89 | 86 | 86 | 91 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 146 | 149 | 150 | 140 | 122 | 124 |
| Humidity/Visibility | 141 | 142 | 138 | 129 | 117 | 122 |
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. |
