Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 194 | 173 | 214 | 214 | 227 | 212 |
| Tmin | 171 | 168 | 207 | 219 | 229 | 209 |
| Duration of sunshine | 86 | 77 | 105 | 115 | 110 | 114 |
| Precipitation | 145 | 119 | 158 | 172 | 167 | 164 |
| Humidity/Visibility | 90 | 82 | 102 | 111 | 116 | 114 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 217 | 217 | 214 | 207 | 225 | 225 |
| Tmin | 219 | 214 | 201 | 199 | 197 | 213 |
| Duration of sunshine | 98 | 109 | 87 | 99 | 95 | 91 |
| Precipitation | 175 | 185 | 185 | 187 | 193 | 214 |
| Humidity/Visibility | 112 | 112 | 107 | 104 | 109 | 114 |
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. |
