Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 134 | 123 | 126 | 130 | 142 | 135 |
| Tmin | 140 | 123 | 132 | 132 | 141 | 134 |
| Duration of sunshine | 62 | 57 | 0 | 30 | 124 | 90 |
| Precipitation | 171 | 148 | 155 | 160 | 168 | 153 |
| Humidity/Visibility | 106 | 95 | 103 | 101 | 110 | 106 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 131 | 142 | 162 | 148 | 140 | 153 |
| Tmin | 149 | 139 | 165 | 165 | 143 | 168 |
| Duration of sunshine | 31 | 62 | 90 | 31 | 0 | 62 |
| Precipitation | 160 | 172 | 178 | 182 | 207 | 195 |
| Humidity/Visibility | 118 | 114 | 130 | 119 | 104 | 125 |
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. |
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