Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 37 | 49 | 47 | 50 | 51 | 62 |
| Tmin | 52 | 56 | 51 | 60 | 58 | 73 |
| Duration of sunshine | 48 | 52 | 49 | 58 | 57 | 68 |
| Precipitation | 71 | 62 | 62 | 63 | 80 | 95 |
| Humidity/Visibility | 43 | 49 | 46 | 48 | 49 | 57 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 77 | 81 | 67 | 41 | 65 | 76 |
| Tmin | 75 | 87 | 71 | 68 | 61 | 84 |
| Duration of sunshine | 73 | 84 | 66 | 61 | 63 | 83 |
| Precipitation | 98 | 96 | 99 | 93 | 99 | 104 |
| Humidity/Visibility | 68 | 73 | 61 | 50 | 62 | 74 |
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. |
