Weather Instruments

TSW Identify weather instruments and explain how each is used in gathering weather data and making

forecasts (thermometer, rain gauge, barometer, wind vane, anemometer, hygrometer).

How do we measure weather?

5 most common instruments:

1. Thermometer2. Weather vane3. Barometer4. Hygrometer5. Anemometer6. Rain gauge

Thermometer

• Measures the air temperature

• Most thermometers are closed glass tubes containing liquids such as alcohol or mercury.

• When air around the tube heats the liquid, the liquid expands and moves up the tube. A scale then shows what the actual temperature is.

Thermometer

Let’s try using one.

Weather Vane

• Measures wind direction

• Knowing the direction of the wind is an important part in predicting the weather.

• It points in the direction it is blowing from.

Weather Vane

Barometer

• Measures air pressure (BAP)

• It tells you whether or not the pressure is rising or falling. A rising barometer means sunny and dry conditions (H), while a falling barometer means stormy and wet conditions(L).

Barometer

Hygrometer

• Measures humidity. (H-H)

• It determines how quickly water evaporates from a wet surface and measures the water vapor content of air.

Hygrometer

Anemometer

• Measures wind speed. (Mom running fast)

• The cups catch the wind, turning a dial attached to the instrument. The dial shows the wind speed.

Anemometer

Rain Gauge

• Measures the amount of rain that has fallen over a specific time period.

• Using measurements on the side of the rain gauge, you can see how many inches it rained.