1. Weather.com – Weather Maps

2. Elements of Weather
Pages

3. Do Now…
Q: Name the element of weather that was assigned to you and explain what you learned from your research A:

4. Today we will be able to….
Collect and interpret weather data. (i.e. air pressure, precipitation, temperature, wind direction and speed, humidity) and predict future weather conditions using this data.

5. What is weather?
Weather is the condition of Earth’s atmosphere at a certain time and place
People talk about weather by describing factors such as temperature, humidity, precipitation, air pressure, wind and visibility
Able to observe and MEASURE these six elements

6. How do we measure temperature?
Temperature is a measure of how hot or cold something is
A thermometer uses a liquid such as alcohol or mercury to display the temperature.
When air gets warmer, the liquid expands and rises in the tube. Cooler air causes the liquid to contract and fill less of the tube.

8. How do we measure humidity?
Humidity is the amount of water vapor in the air
Measured using a psychrometer
Relative humidity is the amount of water vapor in the air compared to the amount of water vapor needed to reach saturation (dew forms at 100%)
Dew point = when water vapor turns into liquid water

10. How do we measure precipitation?
Precipitation is any form of water that falls to Earth’s surface from clouds (rain, snow, hail, and sleet)
Measured using a rain gauge or meter stick
Air temperature determines which type of precipitation falls to Earth’s surface
Two air masses meet; mixing of temperatures produces precipitation and winds (this is called a FRONT)

12. How do we measure air pressure?
Air pressure = the force of which air molecules push on an area
We don’t feel the weight because air pushes in all directions
Air pressure and density are related; they both decrease with altitude
Measured using a barometer
Low = storms, High = clear skies

13. How do we measure air pressure?
A high-pressure system forms when an air mass cools; bring dry, clear weather
A low-pressure system forms where air masses join; bring precipitation
Winds move from an area of high pressure to an area of low pressure; pressure affects wind direction and wind speed

14. How do we measure air pressure?

15. How do we measure winds?
Wind is air that moves horizontally, or parallel to the ground
Caused by the uneven heating of the earth and air pressure differences (convection)
Measured with an anemometer (speed) or a wind vane (direction)

17. How do we measure visibility?
Visibility is a measure of the transparency of the atmosphere; how far we can see…
Poor visibility can be the result of air pollution or fog; dangerous for travel; ex: dense fog obstructs a driver’s view
Measured by a transmissometer

19. Element of Weather Measuring Instrument Temperature Thermometer
Humidity
Hygrometer, Psychrometer
Precipitation
Rain Gauge, Meter Stick
Air Pressure
Barometer
Wind
Anemometer, Wind Vane
Visibility
Transmissometer

20. Solo Dolo…..MOUTH’S CLOSED
On page 227, complete lesson review

21. EXIT TickEt
Name each element of weather and the instrument that measures it