Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1114 | 1007 | 1113 | 1079 | 1112 | 1079 |
| Tmin | 1115 | 1004 | 1112 | 1078 | 1116 | 1077 |
| Duration of sunshine | 185 | 163 | 182 | 178 | 186 | 177 |
| Precipitation | 188 | 168 | 186 | 181 | 186 | 180 |
| Humidity/Visibility | 184 | 167 | 182 | 179 | 183 | 177 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1110 | 1115 | 1105 | 1132 | 1106 | 1146 |
| Tmin | 1109 | 1117 | 1106 | 1130 | 1106 | 1145 |
| Duration of sunshine | 178 | 187 | 205 | 199 | 205 | 215 |
| Precipitation | 184 | 190 | 209 | 212 | 211 | 219 |
| Humidity/Visibility | 180 | 184 | 204 | 203 | 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. |
