Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 119 | 100 | 107 | 101 | 96 | 76 |
| Tmin | 121 | 108 | 119 | 105 | 116 | 103 |
| Duration of sunshine | 241 | 241 | 262 | 278 | 250 | 286 |
| Precipitation | 130 | 114 | 128 | 124 | 125 | 123 |
| Humidity/Visibility | 118 | 105 | 114 | 108 | 111 | 99 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 96 | 112 | 103 | 105 | 106 | 110 |
| Tmin | 109 | 118 | 107 | 112 | 113 | 117 |
| Duration of sunshine | 250 | 298 | 310 | 318 | 256 | 294 |
| Precipitation | 130 | 124 | 125 | 128 | 128 | 134 |
| Humidity/Visibility | 112 | 118 | 112 | 108 | 111 | 116 |
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. |
