Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 2171 | 1983 | 2201 | 2129 | 2199 | 2109 |
| Tmin | 2173 | 1982 | 2200 | 2129 | 2200 | 2108 |
| Duration of sunshine | 186 | 166 | 185 | 178 | 186 | 178 |
| Precipitation | 186 | 169 | 186 | 181 | 186 | 180 |
| Humidity/Visibility | 184 | 168 | 185 | 179 | 185 | 179 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 2189 | 2200 | 2157 | 2223 | 2155 | 2232 |
| Tmin | 2190 | 2203 | 2158 | 2226 | 2157 | 2231 |
| Duration of sunshine | 180 | 188 | 208 | 208 | 206 | 216 |
| Precipitation | 184 | 190 | 209 | 214 | 209 | 217 |
| Humidity/Visibility | 181 | 185 | 207 | 210 | 206 | 214 |
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. |
