Transcript weathe~3 - Rosierulescience

Chapter 16
Section 4
Weather, Weather Maps and
Forecasting
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Weather
 Weather: The daily conditions of a particular area:
temp, rain, pressure, wind, etc.
 Weather Forecast- A prediction about future
weather conditions based on weather data.
 Meteorologist: A scientist who studies the weather
and brings us the weather forecast, like you see
on the news. They use information they gather
from many sources to predict the weather.
 Meteorology- the science of studying weather
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Weather Forecasting Technology

Weather Balloon
Carry electronic equipment that can measure weather conditions as
high as 30 km above the Earth’s surface.
They measure temperature, air pressure and relative humidity.
They can also measure wind speed and direction.

Thermometer
Measures temperature

Barometer
Measures air pressure

Psychrometer
An instrument used for measuring the water vapor content of the
atmosphere; a type of hygrometer.
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Weather Forecasting Technology
 Windsock
Cone shaped cloth bag; measures wind direction
 Anemometer
Measures wind speed
 Radar
Finds location, movement and amount of precipitation.
Can also predict kind of precipitation
Doppler Radar is used by local T.V. stations to track
precipitation.
 Weather Satellite
Orbit Earth and provide images of weather systems.
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Weather Instruments
Anemometer
Wind Sock
Thermometer
Barometer
Doppler
Radar
Weather
Satellite
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Weather Map
A weather map can show many different
things.
 Temperature
 High Pressure (clear)
 Low Pressure (cloudy)
 Isobars
 Rain/Snow
 Fog
 Warm Front
 Cold Front
 Severe Weather- Hurricanes
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ISOBARS- Certain weather maps allow us to view High and Low pressure
systems that control the weather. An isobar is a line connecting locations of
equal barometric pressure. Isobar maps show where pressures are relatively
high and low, and show us where pressure changes are gradual or dramatic
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over a distance.
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Weather Map Symbols
Cold Front
High Pressure
Clear Weather
Warm Front
Low Pressure
Cloudy Weather
Occluded Front
Isobars:
Stationary Front
Show equal
Lines of
Pressure.
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Station Model
•All over the United States, hundreds of weather observations are
taken several times during the day. These stations collect information
such as temperature, pressure, dew point, etc.
•Meteorologists need a way to get all of this detailed information into
the smallest area possible on a weather map, so that several stations
can be plotted for the same observation time on the same map, thus
giving a ‘big picture’ of what the weather is doing at a snapshot in
time.
•Thus, the need for the station model. The following exercise will
show how to translate weather information to and from a station
model, and then you will both decode and encode station models on
your own.
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Station
Model

77: Temperature
68: Dewpoint

998: Pressure, to the nearest tenth of a millibar. Add either a 10 or 9 in front based on which would bring the value closer to
1000. The pressure here is 999.8 millibars (mb).

-03: Pressure tendency the last 3 hours, to the nearest tenth of a millibar. The pressure here has fallen .3 mb the last 3
hours

Middle Circle (filled in w/ mostly black): Cloud cover. It's mostly black showing that this station is mostly cloudy.
Technically, this represents a broken sky with 7/8 of the sky covered with clouds.

Black line, extending from circle: Wind barb. It points to where the wind is coming from. The wind here is from the
southwest, hence a southwest wind. The two lines extending represent 20 knot winds with each line representing 10 knots.

Symbol between 77 and 68: This is the present weather field and in this case shows that there is a thunderstorm occuring
at the station


Symbol next to -03: That line is the pressure tendency. The 1st hour the pressure was steady, then fell the last two hours.
Triangle(with a dot above it): Previous weather, or the weather one hour ago. In this case it was a light rain shower.
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Station Models
 Click Below to see the different type of
symbols used on a station model.
 http://www.hpc.ncep.noaa.gov/html/stationpl
ot_printer.html
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National Weather Service (NWS)
 From the NWS website you can view any
kind of weather related information.
 You can even see river stages and air
quality.
National Oceanic and Atmospheric Administration's
National Weather Service
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National Oceanic and Atmospheric
Administration (NOAA)
 www.noaa.gov
 NOAA collects and analyzes weather data.
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Assignment:
 Define terms 1-11 using your notes.
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