Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 303 | 277 | 297 | 306 | 326 | 314 |
| Tmin | 361 | 326 | 349 | 361 | 374 | 359 |
| Duration of sunshine | 180 | 188 | 240 | 249 | 259 | 223 |
| Precipitation | 98 | 95 | 95 | 133 | 134 | 127 |
| Humidity/Visibility | 89 | 80 | 89 | 110 | 106 | 109 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 319 | 309 | 287 | 292 | 286 | 301 |
| Tmin | 363 | 357 | 339 | 357 | 356 | 377 |
| Duration of sunshine | 182 | 209 | 210 | 219 | 220 | 268 |
| Precipitation | 132 | 134 | 129 | 128 | 128 | 128 |
| Humidity/Visibility | 100 | 102 | 100 | 95 | 102 | 118 |
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. |
