Climate is the statistics of weather, usually over a 30-year interval. It is measured by assessing the patterns of variation in temperature, humidity, atmospheric pressure, wind, precipitation, atmospheric particle count and other meteorological variables in a given region over long periods of time.
Once you have the saturation vapor pressure and the actual vapor pressure, relative humidity can be computed by dividing the actual vapor pressure by the saturation vapor pressure and then multiplying by 100 to convert the quantity to a percent. (7) Relative Humidity(RH) in percent =(E/Es)*100.
The tables give the averages of daily readings for the highest and lowest relative humidity levels. Relative humidity measures the actual amount of moisture in the air as a percentage of the maximum amount of moisture the air can hold. All the numbers here are based on weather data collected from 1961 to 1990. You can jump to a separate table for each country: England, Wales, Scotland and Northern Ireland.