Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 929 | 863 | 951 | 921 | 953 | 919 |
| Tmin | 897 | 831 | 920 | 894 | 926 | 895 |
| Duration of sunshine | 124 | 141 | 155 | 150 | 186 | 120 |
| Precipitation | 530 | 476 | 527 | 509 | 527 | 510 |
| Humidity/Visibility | 168 | 152 | 163 | 165 | 171 | 162 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 947 | 947 | 939 | 970 | 955 | 956 |
| Tmin | 927 | 927 | 913 | 943 | 926 | 954 |
| Duration of sunshine | 155 | 124 | 180 | 217 | 180 | 217 |
| Precipitation | 526 | 527 | 537 | 549 | 540 | 532 |
| Humidity/Visibility | 169 | 171 | 191 | 188 | 190 | 178 |
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. |
