Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 680 | 615 | 661 | 653 | 659 | 657 |
| Tmin | 679 | 616 | 677 | 658 | 680 | 659 |
| Duration of sunshine | 307 | 279 | 321 | 284 | 313 | 385 |
| Precipitation | 124 | 113 | 124 | 121 | 124 | 120 |
| Humidity/Visibility | 123 | 111 | 121 | 117 | 122 | 119 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 680 | 679 | 657 | 670 | 643 | 682 |
| Tmin | 676 | 676 | 654 | 674 | 653 | 678 |
| Duration of sunshine | 306 | 338 | 327 | 269 | 282 | 304 |
| Precipitation | 127 | 126 | 120 | 122 | 122 | 124 |
| Humidity/Visibility | 122 | 122 | 117 | 118 | 118 | 124 |
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. |
