Search Farmonline Weather Help

search for in

Understanding the Weather

What is relative humidity?

Relative humidity is the ratio of the amount of water vapour in the air to the amount it could hold if it was saturated. As temperature increases, the amount of water vapour the air can hold increases. Therefore, relative humidity decreases with increasing temperature assuming the amount of water vapour in the air stays the same. As a result, relative humidity goes through a diurnal cycle inverse to temperature, peaking in the early morning and reaching a minimum during the afternoon. For this reason, it is not the best guide to the amount of water vapour in the air - that would be the dew point.

Related Articles

Site search


Enter a postcode or town name for local weather, or text to search the site. » advanced search

Welcome rain spreading across parched SA

16:06 AEST A much-needed burst of wet weather will sweep across the southern half of SA during the next two days, although the useful showers will be accompanied by blustery winds and a wintry chill.

Help with Farmonline Weather