What is humidity?
What is precipitation?
What is air pressure?
The amount of moisture in the air around you. It indicated the likelihood
precipitation, fog, or dew. It is measured with a hygrometer or pyschrometer.
A result of condensation in the atmosphere that falls due to gravity this includes
rain, sleet, hail, or snow. It is measured with a rain gauge.
The amount of force that air molecules push on you or a surface. It is measured
with a barometer.
WEATHER WARM UP
VOCABULARY TO KNOW~
WEATHER TOOLS- INSTRUMENTS NEEDED
TO FORCAST
TEMPERATURE
Measure of the average
amount of motion in particles.
More motion more HEAT.
Measure with a thermometer
in oC or oF
HUMIDITY
Amount of water vapor in the air
It indicated the likelihood precipitation, fog, or dew.
Measure it with a Hygrometer or Sling Psychrometer
It is expressed as a % of water vapor. 45% is
comfortable for humans.
Humidity is to blame for that muggy, steam-room feeling
you experience on certain summer days.
https://www.youtube.com/w
atch?v=g2C6rKAvzbs&index
=1&list=PLs_igQW0dTqFQB
Olq84rWm-e5WHTSkeFn
WIND
Natural movement of air at any speed
Wind speed is measured with an
anemometer
Wind direction is measured with a wind
vane
AIR PRESSURE
Force on an area by
the air molecules
Measure with a
barometer
PRECIPITATION ANY PRODUCT OF THE CONDENSATION OF
ATMOSPHERIC WATER VAPOR THAT FALLS UNDER GRAVITY
Snow (#10): forms when water vapor turns directly into ice without ever
passing through a liquid state.
Hail (#11): frozen water from the cloud that is pushed back up by wind then
covered again, cycle continues.
Sleet: mixture of snow and rain as well as raindrops that freeze on their way
down.
Rain (#12): drops of liquid water fall all the way to the surface of the Earth.
Freezing rain (#13): (glaze) takes place when water droplets become superchilled and do not freeze in air, but rather freeze the instant they strike an
object, such as a road or car.
WEATHER MAPS
Show atmospheric conditions above a large
portion of the Earth's surface. Meteorologists
use weather maps to forecast the weather.
http://wtvr.com/weather/forecast/
Lightning
~Electric discharge
(bright flash of
electricity) from a
Cumulonimbus cloud.
DOPPLER RADARS DETECT CLOUD COVER AND
PRECIPITATION BY USING RADIO WAVES.
http://upload.wikimedia.org/wikipedia/commons/thumb/5/52/Norman_Doppler_Radar_-_NOAA.jpg/800px-Norman_Doppler_Radar_-_NOAA.jpg
NOAA USES SHIPS, SATELLITES, AND PLANES
TO COLLECT INFORMATION ABOUT THE
WEATHER.
What causes the wind to blow?
 Some parts of the Earth receive direct rays from the SUN all year and are
always warm (close to the equator.)
 Other places receive indirect rays, so the climate is colder (near the poles.)
 The rising and sinking of air due to it’s temperature.
 Warm air, which weighs less than cold air, rises. Then, cool air moves in and
replaces the rising warm air.
 High and low pressures moves around
 They all cause the movement of the air molecules.
http://vimeo.com/10879084
ACTIVITY:
COMPLETE YOUR NOTES SHEET:
WRITE YOUR OWN WEATHER FORECAST FOR
WASHINGTON DC. WHAT WEATHER DO YOU
WANT?!?
DID YOU KNOW?
Hail isn't always round or small
enough to hold in the palm of
your hand.Some of these hard
chunks of ice are elongated or
jagged. They are mostly the size of
gumballs, golf balls, or even
baseballs. But the largest hailstone
ever recorded in the United States
landed in Coffeyville, Kansas, in
1970. Measuring 17.3 inches around,
this monster ice crystal weighed 1.67
pounds. The National Center for
Atmospheric Research held on to it
and made models. Imagine what it
would have felt like to be hit on the
head with that hailstone!
Hurricanes almost never occur in Europe. In
fact, there was no word for hurricane in English
until Europeans settled in the Caribbean Islands.
The Spanish took the name of a storm god,
Huracán, from the Taino Indians. These storms are
also known as typhoons, cyclones, and severe
cyclonic storms when they occur in other oceans.
Lightning does strike more than once, even
when it comes to people.Your chances of being
hit by lightning are very low. Some estimates put
the odds at 1 in 350,000. Others at 1 in 600,000.
Roy C. Sullivan, a park ranger, is the only person
known to have been struck by lightning seven
times. He survived each time, but not unscathed.
He lost a toenail, had his eyebrows burned off and
his hair seared twice, and even suffered shoulder
and leg burns.