Transcript Weather Review

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?
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
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
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
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
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.
Fronts
Cold 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
Fronts
Stationary 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
Fronts
Warm 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.
Fronts
Occluded
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.
El Nino
 an abnormal warming of surface ocean
waters in the eastern tropical Pacific.