Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 440 | 434 | 487 | 503 | 517 | 489 |
| Tmin | 447 | 444 | 491 | 503 | 520 | 501 |
| Duration of sunshine | 103 | 78 | 90 | 86 | 90 | 82 |
| Precipitation | 157 | 142 | 171 | 177 | 165 | 149 |
| Humidity/Visibility | 139 | 124 | 134 | 118 | 119 | 129 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 515 | 533 | 494 | 518 | 502 | 525 |
| Tmin | 520 | 537 | 496 | 517 | 500 | 519 |
| Duration of sunshine | 85 | 105 | 87 | 83 | 78 | 85 |
| Precipitation | 159 | 193 | 201 | 186 | 170 | 170 |
| Humidity/Visibility | 110 | 131 | 157 | 156 | 127 | 142 |
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. |
