Weather Instuments
Learning Targets


I can identify weather instruments
and explain how each is used in
gathering weather data and explain
how each is used in gathering
weather data.
I can use observations and records
of weather conditions to predict
weather patterns.
What is weather?
The Most Common Weather Tools
Are:
• Thermometer
• Wind Vane
• Anemometer
• Barometer
• Rain Gauge
• Hygrometer / Psychrometer
Thermometer
Thermometers measure air
temperatures. It tells us
how hot or cold the
temperature is.
Thermometers work
because matter expands
when heated. Most
thermometers are closed
glass tubes containing
liquids such as alcohol.
Barometer
A barometer
measures air
pressure.
 There are two
types of
Barometers:
Mercury
Barometer and
Aneroid
Barometer.

A Mercury
Barometer consists
of a glass tube
inserted into a dish
of mercury or
colored denatured
alcohol.
 *(If you build your
own, don’t use
mercury)


The surrounding air
presses down on the
mercury in the dish
and forces some of
the mercury up into
the tube. The
height to which the
mercury rises in the
tube is directly
proportional to the
atmospheric
pressure.
Psychrometer
or
Hygrometer

A psychrometer
measures the
humidity of the
air. One of the
two
thermometers
has a wick (cloth
cover) which is
dipped in
distilled water.


Evaporation of water
from the wick on the
wet bulb
thermometer leads
to cooling.
Using a Relative
Humidity Table, the
temperature
difference between
the two
thermometers gives
the relative humidity
of the air (in
percent).
Anemometer
An Anemometer
measures the
wind speed. The
cups catch the
winds, turning a
dial attached to
the instrument.
 Think you could
build one of
these?

Rain Gauge
A rain gauge measures the
amount of precipitation that
has fallen.
Thermograph
A thermograph is a tool used to make a
graph of the ups and downs of
temperature.
Radar

A weather radar is used to locate
precipitation, calculate its
motion, estimate its type (rain,
snow, hail, etc.), and forecast its
future position and intensity.

Modern weather radars are
mostly doppler radars, capable of
detecting the motion of rain
droplets in addition to intensity
of the precipitation.
Weather Vane or Wind Vane

A vane designed to indicate the
direction in which the wind is
blowing. (N, NE, S, SE, W, SW, SE)
Other Tools
Weather Satellites (GOES)
Orbits Earth in outer
space.
• Sends back pictures of the atmosphere.
• Pictures large areas all at the same time
• Can detect movement of ice fields.
Weather Balloons



Gather data for weather stations at
all levels of the troposphere.
Released on an organized schedule
from hundreds of stations at the
same time each day.
Balloon, Parachute, Sensor Array
Weather Tool Usage


Weather Tools are used by
a meteorologist.
A meteorologist is an individual with
specialized education who uses
scientific principles to explain,
understand, observe or forecast the
earth's atmospheric phenomena
and/or how the atmosphere affects
the earth and life on the planet.