Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1187 | 1082 | 1207 | 1168 | 1206 | 1169 |
| Tmin | 1191 | 1087 | 1206 | 1169 | 1208 | 1165 |
| Duration of sunshine | 399 | 357 | 430 | 419 | 432 | 414 |
| Precipitation | 192 | 178 | 187 | 181 | 186 | 182 |
| Humidity/Visibility | 182 | 158 | 185 | 179 | 184 | 178 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1201 | 1205 | 1191 | 1227 | 1184 | 1238 |
| Tmin | 1203 | 1210 | 1190 | 1228 | 1185 | 1236 |
| Duration of sunshine | 458 | 431 | 474 | 512 | 465 | 489 |
| Precipitation | 191 | 192 | 218 | 216 | 212 | 221 |
| Humidity/Visibility | 180 | 183 | 204 | 206 | 206 | 213 |
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. |
