The direction of the arrow shows the direction from which the wind is blowing.
25 19 10 35 15 20 1007
The number indicates the speed of the wind in kilometres per hour.
SATURDAY AFTERNOON 30
Wind is displayed as a white arrow.
Examine the weather map. What speeds are the winds (i) over County Wexford, (ii) off the west coast of Kerry, (iii) over the east coast of Scotland, (iv) off the east coast of England? You may use Google Maps to help you locate each place.
5 Humidity
Humidity is the amount of water vapour in the air. A hygrometer (figures 7 and 8) is used to measure relative humidity, which is expressed as a percentage.
Humidity and the Weather
When weather forecasters speak about humidity, they do so using the term ‘relative humidity’.
Key Words
Water vapour Hygrometer
Fun Fact!
On a hot, humid day it often feels hotter than it actually is. This is because there is so much water vapour in the air that our sweat cannot evaporate to help cool us.
The term ‘humidity’ refers to water vapour in the air. Warm air can hold more water vapour than cool air can. When the air can hold no more water vapour, it is said to be saturated. Any extra water vapour then condenses into tiny droplets to form clouds.
