Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 402 | 363 | 400 | 390 | 401 | 402 |
| Tmin | 399 | 362 | 403 | 386 | 398 | 401 |
| Duration of sunshine | 124 | 141 | 186 | 180 | 124 | 150 |
| Precipitation | 99 | 96 | 99 | 94 | 102 | 106 |
| Humidity/Visibility | 88 | 80 | 88 | 87 | 90 | 100 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 428 | 431 | 418 | 426 | 416 | 430 |
| Tmin | 430 | 428 | 420 | 429 | 411 | 431 |
| Duration of sunshine | 155 | 217 | 180 | 217 | 150 | 186 |
| Precipitation | 131 | 134 | 122 | 127 | 128 | 133 |
| Humidity/Visibility | 119 | 118 | 116 | 114 | 115 | 120 |
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. |
