Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1065 | 963 | 1078 | 1042 | 1080 | 1030 |
| Tmin | 1070 | 970 | 1071 | 1044 | 1082 | 1040 |
| Duration of sunshine | 131 | 119 | 125 | 122 | 135 | 127 |
| Precipitation | 155 | 142 | 157 | 163 | 157 | 166 |
| Humidity/Visibility | 145 | 131 | 144 | 133 | 137 | 128 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1072 | 1096 | 1064 | 1097 | 1065 | 1068 |
| Tmin | 1073 | 1091 | 1062 | 1091 | 1060 | 1071 |
| Duration of sunshine | 134 | 151 | 153 | 140 | 96 | 128 |
| Precipitation | 168 | 186 | 186 | 186 | 179 | 165 |
| Humidity/Visibility | 138 | 152 | 155 | 162 | 141 | 140 |
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. |
