Weather Prediction

1
Weather Prediction

• How do weather forecasters predict the weather?
• How has technology helped to improve weather
  forecasts?
• What can be learned from the information on
  weather maps?

2
How do weather forecasters predict the weather?

• Meteorologists- Scientist who studies the causes
  of weather and tries to predict it
• Meteorologists most important tool? RADAR!!!!!
• Current National Doppler Radar Map - USATODAY.com
• NWS radar image from Raleigh/Durham, NC

3
How has technology helped to improve weather
forecasts?

• Technological improvements in gathering weather
  data and using computers have improved the
  accuracy of weather forecasts
• The most recent advancement is the SATELLITE
• Satellite Images - NOAA's National Weather
  Service

4
What can of information is found in the news?

• Current temperature
• Forecast hourly, day, extended
• Alerts
• Sunrise, sunset
• Humidity
• Check weather online

• Air pressure
• Daily highs and lows
• Wind speed and direction
• Record highs and lows
• Severe weather
• Cloud cover

5
What can be learned from the information on
weather maps?

• Standard symbols on weather maps show fronts,
  areas of high and low pressure, type of
  precipitation, and temperatures.
• Weather Map

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Weather Tools

• Psychrometer- measure relative humidity
• Anemometer- measures wind speed
• Barometers- measures air pressure
• Aneroid (without liquid)- accurately describe how
  this barometer functions. Instead of mercury,
  these barometers use a small metal box called an
  aneroid cell. This cell is actually a bellows and
  springs system which expands or contracts as air
  pressure changes.
• Mercury-A column of mercury is inside a glass
  tube sealed at one end. The other end rests in a
  small cup of mercury, called a cistern.

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FrontsCold Front

• transition zone from warm air to cold air
• A cold front is defined as the transition zone
  where a cold air mass is replacing a warmer air
  mass.
• When a cold front passes through, temperatures
  can drop more than 15 degrees within the first
  hour

8
FrontsStationary Front

• a front that is not moving
• When a warm or cold front stops moving, it
  becomes a stationary front. Once this boundary
  resumes its forward motion, it once again becomes
  a warm front or cold front.
• A stationary front is represented by alternating
  blue and red lines with blue triangles pointing
  towards the warmer air and red semicircles
  pointing towards the colder air

9
FrontsWarm Front
transition zone from cold air to warm air A warm front is defined as the transition zone where a warm air mass is replacing a cold air mass. Warm fronts generally move from southwest to northeast and the air behind a warm front is warmer and more moist than the air ahead of it. When a warm front passes through, the air becomes noticeably warmer and more humid than it was before.
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FrontsOccluded Front

• when a cold front overtakes a warm front
• A developing cyclone typically has a preceding
  warm front (the leading edge of a warm moist air
  mass) and a faster moving cold front (the leading
  edge of a colder drier air mass wrapping around
  the storm).
• North of the warm front is a mass of cooler air
  that was in place before the storm even entered
  the region.

11
El Nino

• an abnormal warming of surface ocean waters in
  the eastern tropical Pacific.