Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 500 | 433 | 486 | 470 | 491 | 472 |
| Tmin | 502 | 434 | 489 | 484 | 489 | 473 |
| Duration of sunshine | 205 | 176 | 231 | 195 | 153 | 125 |
| Precipitation | 127 | 117 | 127 | 142 | 135 | 147 |
| Humidity/Visibility | 105 | 73 | 86 | 88 | 98 | 89 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 499 | 499 | 499 | 496 | 457 | 497 |
| Tmin | 498 | 506 | 499 | 500 | 461 | 498 |
| Duration of sunshine | 195 | 199 | 293 | 265 | 181 | 268 |
| Precipitation | 163 | 163 | 190 | 179 | 148 | 148 |
| Humidity/Visibility | 98 | 100 | 112 | 103 | 66 | 94 |
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. |
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