Weather Tools
6.4.5 Use appropriate instruments and tools to
collect weather data (including wind speed and
direction, air temperature, humidity, and air
pressure.
?
Essential Question
 What weather instruments and tools do scientists use to
measure weather and how do they work?
Anemometer
 Measures the wind speed in miles
per hour.
 To use it, count the number of
rotations in one minute (rpm).
 You can then convert that to miles
per hour.
 That’s a complex formula. ;)
Wind Vane
 A tool used to measure wind
direction.
 Sometimes referred to as a
wind-weather vane or a wind
sock.
 Wind direction is described by
the direction from which the
wind is blowing as indicated by
the pointer.
Sling Psychrometer
 A two-thermometer instrument also referred to as a wet-dry
bulb;
 Used to measure the relative humidity (the amount of water
vapor in the air).
 Temperature readings are converted using a relative humidity
table.
How do I use it?
Find the dry bulb reading.
2. Find the wet bulb reading.
3. Subtract the wet bulb from the dry bulb. (Difference)
4. Use the chart to calculate the relative humidity.
1.
Practice using a sling psychrometer.
1.
Use the following table.
Trial #
1
2
3
4
5
6
7
8
9
10
Dry Bulb
Wet Bulb
Difference b/w
Humidity
Trial #1
Dry Bulb
Wet Bulb
Trial #2
Dry Bulb
Wet Bulb
Trial #3
Dry Bulb
Wet Bulb
Trial #4
Dry Bulb
Wet Bulb
Trial #5
Dry Bulb
Wet Bulb
Trial # 6
Dry Bulb
Wet Bulb
Trial # 7
Dry Bulb
Wet Bulb
Trial # 8
Dry Bulb
Wet Bulb
Trial # 9
Dry Bulb
Wet Bulb
Trial # 10
Dry Bulb
Wet Bulb
What do you notice about the relationship
between the readings and the humidity?
Barometer
 Measures the air pressure in inches
of mercury or millibars (mb)
 There are two pointers:
 The one inside the glass is the
current reading and it moves
according to the air pressure.
 The one on top is the set
pointer. You move it so you will
know tomorrow what the
setting was today.
Using the Barometer
Find the current reading. That would be the full arrow.
2. Read the set pointer. That would be the half arrow.
3. Compare the current reading to the set pointer
1.



If the current reading is higher, then the air pressure is rising
indicating fairer weather on the way.
If the current reading is lower, then the air pressure is falling
indicating rainy conditions may be coming.
https://www.youtube.com/watch?v=i2UKTpIQG6M
Thermometer
 A tool used to measure air
temperature in degrees
Fahrenheit or Celsius.
 To determine the
temperature, read to the
highest mark on the scale as
indicated by the red dye.
Rain Gauge
 A tool used for measuring the
amount of precipitation in
inches or centimeters.
Using the Rain Gauge

Rain gauges work just like a graduated cylinder, so measure to
the meniscus (the dipped portion).