Forecasting the Weather 3/24/14
16-4 pgs. 440-443
IN: How do

meteorologists
forecast the
weather?
TERMS AND OBJECTIVES
TERMS:
themometers barometers
windsock
wind vane anemometer
isobars
 OBJECTIVES:
Describe the different types of instruments
used to take weather measurements.
Explain how to interpret a weather map.
Explain why weather maps are useful.

Cold Front
Weather forecast - a prediction
of weather conditions
(usually over the next 3 to 5
days).
Today
Friday
Saturday
Sunday
Monday
Partly
Cloudy /
Wind
AM
Showers /
Wind
Few
Showers
Sunny
Partly
Cloudy
70°F
58°
61°
71°
76°
High
High
High
High
High
48°
43°
46°
51°
55°
Low
Low
Low
Low
Low
Chance of
Precip:
20%
Chance of
Rain:
30%
Chance of
Rain:
30%
Chance of
Precip:
0%
Chance of
Precip:
0%
Meteorologists use special
tools to measure various
atmospheric conditions
in order to accurately
forecast weather called:
Weather Instruments
Thermometer – instrument
used to measure air
temperature.
Barometer – instrument used
to measure air pressure.
Windsock or Wind vane instrument used to measure
wind direction.
Anemometer – instrument
used to measure wind speed.
Weather in the upper atmosphere
must be studied with more
sophisticated equipment.
Weather balloons - carry
equipment that measures
temperature, air pressure,
and relative humidity as high
as 30 km.
Weather satellites - orbit the
Earth and measure wind
speeds, humidity, and
temperatures at various
altitudes.
The National Weather Service (NWS)
produces weather maps based on
information gathered at about 1,000
weather stations across the U.S.
Each station is represented with a
station model:
Weather maps also include lines called
isobars, which connect points of
equal air pressure. These lines
indicate areas of high or low
pressure.
Weather maps also label fronts, which
along with isobars help to make
accurate weather forecasts.

OUT: Why would a
meteorologist
compare a new
weather map with
one 24 hours ago?