Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1168 | 1093 | 1208 | 1168 | 1195 | 1168 |
| Tmin | 1169 | 1092 | 1208 | 1167 | 1196 | 1169 |
| Duration of sunshine | 100 | 111 | 132 | 146 | 171 | 168 |
| Precipitation | 190 | 168 | 188 | 184 | 188 | 180 |
| Humidity/Visibility | 183 | 165 | 184 | 175 | 181 | 175 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1205 | 1208 | 1190 | 1233 | 1197 | 1238 |
| Tmin | 1209 | 1210 | 1190 | 1234 | 1196 | 1239 |
| Duration of sunshine | 163 | 172 | 171 | 155 | 103 | 101 |
| Precipitation | 186 | 192 | 212 | 223 | 210 | 219 |
| Humidity/Visibility | 180 | 182 | 204 | 207 | 204 | 211 |
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. |
