Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1053 | 976 | 1080 | 1061 | 1104 | 1073 |
| Tmin | 1052 | 975 | 1076 | 1060 | 1102 | 1069 |
| Duration of sunshine | 239 | 242 | 270 | 278 | 268 | 290 |
| Precipitation | 97 | 91 | 103 | 112 | 127 | 129 |
| Humidity/Visibility | 89 | 80 | 88 | 103 | 119 | 115 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1099 | 1104 | 1062 | 1109 | 1073 | 1114 |
| Tmin | 1096 | 1102 | 1057 | 1109 | 1074 | 1108 |
| Duration of sunshine | 268 | 302 | 320 | 298 | 227 | 236 |
| Precipitation | 131 | 130 | 123 | 126 | 126 | 132 |
| Humidity/Visibility | 121 | 119 | 115 | 115 | 114 | 120 |
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. |
