Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 317 | 281 | 316 | 312 | 325 | 306 |
| Tmin | 325 | 285 | 322 | 322 | 325 | 313 |
| Duration of sunshine | 186 | 254 | 217 | 210 | 186 | 210 |
| Precipitation | 93 | 85 | 95 | 109 | 124 | 124 |
| Humidity/Visibility | 92 | 84 | 91 | 104 | 123 | 118 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 319 | 316 | 306 | 340 | 333 | 346 |
| Tmin | 323 | 320 | 307 | 341 | 336 | 350 |
| Duration of sunshine | 248 | 310 | 210 | 248 | 150 | 217 |
| Precipitation | 126 | 127 | 120 | 122 | 120 | 124 |
| Humidity/Visibility | 122 | 122 | 118 | 117 | 118 | 123 |
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. |
