Number of days available for climatic review
| Parameter | Jan | Feb | Mar | Apr | May | Jun |
| Tmax | 1079 | 977 | 1075 | 1045 | 1076 | 1052 |
| Tmin | 1078 | 971 | 1078 | 1042 | 1077 | 1053 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 93 | 90 | 94 | 94 | 95 | 104 |
| Humidity/Visibility | 92 | 83 | 92 | 89 | 91 | 101 |
| Parameter | Jul | Aug | Sep | Oct | Nov | Dec |
| Tmax | 1102 | 1101 | 1075 | 1105 | 1072 | 1102 |
| Tmin | 1104 | 1106 | 1074 | 1100 | 1068 | 1103 |
| Duration of sunshine | 0 | 0 | 0 | 0 | 0 | 0 |
| Precipitation | 129 | 129 | 120 | 123 | 122 | 127 |
| Humidity/Visibility | 120 | 120 | 117 | 117 | 117 | 119 |
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. |
