Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 726 | 661 | 735 | 707 | 730 | 712 |
| Tmin | 736 | 665 | 735 | 708 | 736 | 708 |
| Duration of sunshine | 334 | 303 | 363 | 408 | 330 | 322 |
| Precipitation | 156 | 140 | 158 | 150 | 155 | 150 |
| Humidity/Visibility | 143 | 131 | 145 | 134 | 143 | 140 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 734 | 768 | 753 | 759 | 712 | 741 |
| Tmin | 741 | 763 | 766 | 764 | 734 | 737 |
| Duration of sunshine | 361 | 422 | 397 | 398 | 391 | 367 |
| Precipitation | 155 | 190 | 209 | 206 | 167 | 157 |
| Humidity/Visibility | 148 | 174 | 188 | 180 | 155 | 149 |
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. |
