Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1224 | 1120 | 1236 | 1198 | 1239 | 1200 |
| Tmin | 1226 | 1121 | 1238 | 1197 | 1240 | 1199 |
| Duration of sunshine | 434 | 391 | 402 | 418 | 403 | 388 |
| Precipitation | 186 | 168 | 186 | 181 | 188 | 180 |
| Humidity/Visibility | 185 | 167 | 184 | 179 | 184 | 179 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1238 | 1238 | 1228 | 1262 | 1226 | 1273 |
| Tmin | 1238 | 1241 | 1228 | 1260 | 1227 | 1272 |
| Duration of sunshine | 495 | 497 | 478 | 455 | 417 | 404 |
| Precipitation | 186 | 190 | 212 | 217 | 210 | 217 |
| Humidity/Visibility | 184 | 184 | 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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