World

Europe

Manchester





Number of days available for climatic review

ParameterJanFebMarAprMayJun
Tmax114610661178113811701140
Tmin114810661178113911741137
Duration of sunshine248254310270310300
Precipitation186169187181186180
Humidity/Visibility185168185179185179


ParameterJulAugSepOctNovDec
Tmax117511761162120011671206
Tmin117711791163120111681209
Duration of sunshine310310300310270279
Precipitation186190212215210217
Humidity/Visibility184185207210207214


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.