Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1101 | 1002 | 1116 | 1078 | 1106 | 1057 |
| Tmin | 1102 | 1000 | 1115 | 1076 | 1107 | 1056 |
| Duration of sunshine | 372 | 335 | 401 | 414 | 465 | 417 |
| Precipitation | 186 | 169 | 187 | 181 | 186 | 180 |
| Humidity/Visibility | 185 | 168 | 185 | 179 | 185 | 178 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1108 | 1115 | 1099 | 1140 | 1106 | 1147 |
| Tmin | 1106 | 1117 | 1100 | 1141 | 1108 | 1147 |
| Duration of sunshine | 427 | 404 | 417 | 455 | 387 | 434 |
| Precipitation | 184 | 190 | 212 | 215 | 209 | 217 |
| Humidity/Visibility | 181 | 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. |
