Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1145 | 1066 | 1177 | 1152 | 1197 | 1166 |
| Tmin | 1149 | 1066 | 1176 | 1155 | 1195 | 1168 |
| Duration of sunshine | 211 | 224 | 215 | 250 | 275 | 261 |
| Precipitation | 93 | 86 | 97 | 108 | 130 | 122 |
| Humidity/Visibility | 91 | 84 | 90 | 104 | 122 | 119 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1206 | 1207 | 1155 | 1202 | 1165 | 1209 |
| Tmin | 1207 | 1208 | 1158 | 1204 | 1168 | 1209 |
| Duration of sunshine | 273 | 273 | 264 | 267 | 263 | 272 |
| Precipitation | 125 | 127 | 120 | 121 | 121 | 125 |
| Humidity/Visibility | 122 | 121 | 118 | 118 | 116 | 122 |
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. |
