Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 178 | 155 | 177 | 168 | 167 | 169 |
| Tmin | 174 | 160 | 172 | 172 | 174 | 172 |
| Duration of sunshine | 124 | 141 | 217 | 180 | 186 | 150 |
| Precipitation | 190 | 180 | 200 | 195 | 190 | 195 |
| Humidity/Visibility | 178 | 162 | 178 | 172 | 172 | 171 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 175 | 176 | 198 | 200 | 193 | 201 |
| Tmin | 180 | 180 | 193 | 198 | 201 | 204 |
| Duration of sunshine | 155 | 155 | 210 | 124 | 210 | 186 |
| Precipitation | 192 | 196 | 215 | 216 | 214 | 227 |
| Humidity/Visibility | 180 | 181 | 201 | 203 | 201 | 206 |
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. |
