Forecasting the Weather 3/24/14

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Forecasting the Weather 3/24/14

• 16-4 pgs. 440-443
• IN How do meteorologists forecast the weather?

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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.

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Cold Front
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• 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
70F 58 61 71 76
High High High High High
48 43 46 51 55
Low Low Low Low Low
Chance of Precip20 Chance of Rain30 Chance of Rain30 Chance of Precip0 Chance of Precip0
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• Meteorologists use special tools to measure
  various atmospheric conditions in order to
  accurately forecast weather called
• Weather Instruments

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• Thermometer instrument used to measure air
  temperature.

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• Barometer instrument used to measure air
  pressure.

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• Windsock or Wind vane - instrument used to
  measure wind direction.

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• Anemometer instrument used to measure wind
  speed.

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• Weather in the upper atmosphere must be studied
  with more sophisticated equipment.

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• Weather balloons - carry equipment that measures
  temperature, air pressure, and relative humidity
  as high as 30 km.

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• Weather satellites - orbit the Earth and measure
  wind speeds, humidity, and temperatures at
  various altitudes.

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• The National Weather Service (NWS) produces
  weather maps based on information gathered at
  about 1,000 weather stations across the U.S.

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• Each station is represented with a station model

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• Weather maps also include lines called isobars,
  which connect points of equal air pressure. These
  lines indicate areas of high or low pressure.

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• Weather maps also label fronts, which along with
  isobars help to make accurate weather forecasts.

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• OUT Why would a meteorologist compare a new
  weather map with one 24 hours ago?