Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1162 | 1063 | 1169 | 1136 | 1172 | 1128 |
| Tmin | 1137 | 1034 | 1146 | 1105 | 1145 | 1105 |
| Duration of sunshine | 301 | 327 | 359 | 355 | 335 | 316 |
| Precipitation | 186 | 169 | 186 | 180 | 186 | 179 |
| Humidity/Visibility | 167 | 153 | 166 | 158 | 164 | 156 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1167 | 1176 | 1160 | 1200 | 1165 | 1179 |
| Tmin | 1142 | 1146 | 1130 | 1173 | 1133 | 1175 |
| Duration of sunshine | 363 | 365 | 405 | 443 | 311 | 354 |
| Precipitation | 187 | 189 | 210 | 215 | 212 | 191 |
| Humidity/Visibility | 163 | 164 | 189 | 191 | 187 | 185 |
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. |
