Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 367 | 328 | 366 | 353 | 360 | 355 |
| Tmin | 387 | 333 | 367 | 351 | 359 | 353 |
| Duration of sunshine | 93 | 58 | 62 | 60 | 155 | 120 |
| Precipitation | 343 | 286 | 311 | 303 | 318 | 305 |
| Humidity/Visibility | 124 | 106 | 117 | 113 | 111 | 115 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 364 | 363 | 350 | 364 | 322 | 369 |
| Tmin | 362 | 363 | 353 | 362 | 317 | 364 |
| Duration of sunshine | 93 | 93 | 120 | 186 | 90 | 62 |
| Precipitation | 315 | 316 | 304 | 312 | 302 | 312 |
| Humidity/Visibility | 116 | 117 | 113 | 113 | 82 | 119 |
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. |
