Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 303 | 264 | 298 | 293 | 295 | 303 |
| Tmin | 298 | 267 | 295 | 291 | 302 | 292 |
| Duration of sunshine | 62 | 113 | 93 | 150 | 155 | 60 |
| Precipitation | 109 | 96 | 100 | 102 | 105 | 112 |
| Humidity/Visibility | 53 | 41 | 48 | 46 | 45 | 55 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 320 | 322 | 322 | 321 | 298 | 318 |
| Tmin | 325 | 323 | 322 | 324 | 299 | 326 |
| Duration of sunshine | 155 | 124 | 120 | 124 | 90 | 93 |
| Precipitation | 131 | 129 | 129 | 133 | 130 | 154 |
| Humidity/Visibility | 71 | 65 | 71 | 86 | 76 | 97 |
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. |
