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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.
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- Do you have an explanation of the terminology you use in weather forecasts?
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BoM declares El Niņo over
15:03 AEST The Bureau of Meteorology has officially declared El Niño over and the El Niño Southern Oscillation (ENSO) is now inactive for the first time since 2021, meaning there is no immediate sign of either an El Niño or a La Niña event.
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