How is weather
predicted?
D18-23
V. Martinez
1. Meteorologist
• A meteorologist is a scientist who studies
and measures weather conditions.
2. Thermometer
• A thermometer measures the temperature
of the air.
3. barometer
• A barometer measures air pressure.
4. anemometer
• An anemometer is used to measure wind
speed.
5. Weather Vane
• A weather vane or wind sock is used to
measure wind direction.
6. hygrometer
• A hygrometer measures moisture in the air
or the humidity.
7. Humidity
• Humidity is the amount of water vapor in
the air.
8. Land heats faster than bodies of
water. So the air above land is
usually warmer.
9. What affects humidity?
• 1. The area over which an air mass forms:
An air mass over water has more water
than an air mass over land.
• 2. Temperature: Warm air has more
moisture than cool air.
10. Scientists record weather
information to predict changes in
weather.
11. Small vertical dashes on a
weather map stand for rain.
12. Small stars on a weather map
stand for snow.
13. Rain falls from clouds when
water droplets in the clouds
become big and heavy.
14. On the barometer, when air
pressure drops, the air in the jar
expands and pushes up against the
balloon, causing the craft stick to
point downward.
15. On the barometer, when air
pressure rises, the air surrounding
the jar pushes down on the balloon,
which causes the craft stick to point
up.