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The elements of weather. Temperature is one of the elements of weather. The air temperature can be hot, warm, cool, or cold. The sun's position changes the temperature.

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Temperatures are higher during midday when the sun is high in the sky.

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Temperatures are lower at sunrise and sunset.

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We use a thermometer to measure temperature in degrees Celsius.

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For example, 40 degrees Celsius is very hot and 5 degrees Celsius is cold.

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Wind is another element of weather.

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Wind has two components, wind direction and wind speed. Wind direction is caused by air

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moving from an area of high pressure to an area of low pressure. Pressure is the force exerted

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by the atmosphere on Earth's surface. A weather vane shows wind direction using the cardinal

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points north south east and west for example an east wind blows from east to west an anemometer

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measures wind speed in kilometers per hour for example 40 kilometers per hour is a strong wind

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speed. A category 4 hurricane's wind speed is around 200 kilometers per hour.

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Another element of weather is humidity. Humidity is the amount of water vapor in

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the air. Air with a lot of water vapor is humid. Air with very little water vapor

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is dry when humidity is high you can feel uncomfortable in hot weather you

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feel hotter and in cold weather you feel colder when humidity is low you usually

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feel good but your skin and lips can feel very dry hygrometer measures

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relative humidity as a percentage. At 85% it feels very humid. At 20% it feels very

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dry. Precipitation. Precipitation is an element of weather. Precipitation is

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water in liquid or solid form that falls from the air to the ground. Precipitation

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comes from clouds. Most precipitation starts as ice. This is because even in

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hot weather, the air high in the sky is very cold. Precipitation can fall in four

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forms. Rain, snow, sleet, which is rain that contains ice, and hail, which are

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little balls of ice. We use a rain gauge to measure

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precipitation in millimeters. For example,

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two millimeters per hour is light rain, 20 millimeters per hour is heavy rain.

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The elements of weather are temperature, wind, humidity, and precipitation.