Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 376 | 348 | 379 | 369 | 394 | 395 |
| Tmin | 373 | 339 | 382 | 363 | 387 | 386 |
| Duration of sunshine | 217 | 197 | 186 | 210 | 279 | 240 |
| Precipitation | 96 | 90 | 99 | 98 | 95 | 106 |
| Humidity/Visibility | 89 | 82 | 88 | 84 | 90 | 97 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 425 | 423 | 415 | 399 | 395 | 404 |
| Tmin | 426 | 426 | 408 | 405 | 384 | 405 |
| Duration of sunshine | 217 | 279 | 240 | 248 | 210 | 217 |
| Precipitation | 130 | 128 | 123 | 121 | 121 | 125 |
| Humidity/Visibility | 120 | 119 | 116 | 116 | 117 | 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. |
