Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 701 | 630 | 706 | 677 | 701 | 679 |
| Tmin | 702 | 638 | 705 | 678 | 706 | 681 |
| Duration of sunshine | 52 | 69 | 87 | 85 | 110 | 100 |
| Precipitation | 682 | 615 | 680 | 657 | 682 | 660 |
| Humidity/Visibility | 83 | 75 | 85 | 78 | 85 | 81 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 702 | 730 | 697 | 699 | 678 | 705 |
| Tmin | 708 | 731 | 694 | 700 | 683 | 700 |
| Duration of sunshine | 113 | 135 | 113 | 88 | 56 | 53 |
| Precipitation | 682 | 715 | 694 | 704 | 661 | 687 |
| Humidity/Visibility | 89 | 104 | 102 | 98 | 83 | 86 |
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. |
