World

Europe

Bristol





Number of days available for climatic review

ParameterJanFebMarAprMayJun
Tmax3028312680
Tmin3127313090
Duration of sunshine000000
Precipitation3128313090
Humidity/Visibility-899081042329951998-1992125504000


ParameterJulAugSepOctNovDec
Tmax000122628
Tmin000142830
Duration of sunshine000000
Precipitation000143233
Humidity/Visibility00-21304309120-19923535080


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.