Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1076 | 971 | 1071 | 1037 | 1080 | 1038 |
| Tmin | 1109 | 1002 | 1095 | 1072 | 1109 | 1074 |
| Duration of sunshine | 266 | 238 | 277 | 286 | 290 | 281 |
| Precipitation | 192 | 176 | 200 | 195 | 188 | 188 |
| Humidity/Visibility | 165 | 146 | 163 | 165 | 178 | 172 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1075 | 1076 | 1070 | 1092 | 1069 | 1099 |
| Tmin | 1109 | 1111 | 1099 | 1123 | 1099 | 1137 |
| Duration of sunshine | 290 | 281 | 297 | 302 | 312 | 322 |
| Precipitation | 196 | 198 | 225 | 225 | 226 | 231 |
| Humidity/Visibility | 178 | 171 | 195 | 197 | 192 | 197 |
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. |
