Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 84 | 76 | 78 | 78 | 83 | 96 |
| Tmin | 92 | 82 | 88 | 86 | 92 | 95 |
| Duration of sunshine | 84 | 74 | 80 | 77 | 84 | 80 |
| Precipitation | 97 | 96 | 96 | 101 | 97 | 114 |
| Humidity/Visibility | 66 | 59 | 64 | 62 | 65 | 71 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 94 | 106 | 112 | 117 | 103 | 112 |
| Tmin | 104 | 113 | 119 | 118 | 107 | 120 |
| Duration of sunshine | 78 | 104 | 110 | 117 | 102 | 112 |
| Precipitation | 135 | 130 | 120 | 130 | 126 | 126 |
| Humidity/Visibility | 75 | 81 | 86 | 85 | 80 | 87 |
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. |
