Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1161 | 1065 | 1177 | 1139 | 1176 | 1140 |
| Tmin | 1163 | 1066 | 1178 | 1139 | 1178 | 1139 |
| Duration of sunshine | 402 | 392 | 433 | 419 | 434 | 419 |
| Precipitation | 188 | 169 | 188 | 181 | 186 | 180 |
| Humidity/Visibility | 185 | 168 | 185 | 179 | 184 | 179 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1174 | 1176 | 1167 | 1201 | 1165 | 1210 |
| Tmin | 1177 | 1180 | 1168 | 1200 | 1167 | 1210 |
| Duration of sunshine | 464 | 466 | 478 | 391 | 384 | 466 |
| Precipitation | 186 | 190 | 212 | 215 | 210 | 217 |
| Humidity/Visibility | 184 | 185 | 207 | 210 | 207 | 215 |
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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