Severe Storms
Classified under severe storms are thunderstorms, tornadoes, and hurricanes.
Thunderstorms
• Thunderstorm – produces ________________________ and
_______________________ and possibly heavy rain, gusty
winds, and hail.
– Can be local, single cloud storms, or multiple cells along a
cold front.
• Development of thunderstorms involve 3 stages.
– _______________________ Stage: warm, moist air is
moved upward.
–
–
_______________________ Stage: (about 1 hour later) heavy precipitation begins with gusty winds,
lightning, and hail.
_______________________ Stage: cooling of the air  the storm to die down.
Tornadoes
• Tornadoes – violent ___________________________ that form a
___________________ column of air (vortex) that extends downward from a
cumulonimbus cloud.
• Most form during _______________________________.
• Begins with a strong wind high up in the atmosphere that causes winds lower in
the atmosphere to _____________ horizontally strong thunderstorm
updrafts will cause the ______________________ to tilt until it is standing
upright.
• The intensity of a tornado is based on the wind ______________ and the
estimated _________________. (see page 574 for intensity scale)
Hurricanes
• Hurricane – whirling tropical cyclone that produces
_____________ of at least 119 km (74 mph) in the U.S.
• Develop in late ____________________ when the water
temperatures are warm enough to provide enough
__________________ and
_________________________ to the air.
– Tropical Depression (disturbance) – first stage with several
________________________ clusters and little or no
cloud rotation.
– Tropical Storm – winds begin to ___________________
and thunderstorms progress.
– Hurricane – rotating cloud with winds of ___________
km/hour or more.
• Intensity of a hurricane is based on the wind speeds.
– Category 1 is _______________ with wind speeds of
119 km/hr.
– Category 5 is the most ________________ with wind
speeds above 249 km/hr. (see page 577)
•
•
•
•
Eye – _______________ of the hurricane
where air is subsiding (sinking) and being
warmed.
Eye Wall – the layer of clouds that
__________________ the eye, where
winds are fastest and rainfall is greatest.
Rain Bands – clouds that extend outward
from the eye wall and circulate and
__________________ around the storm
cell.
Storm Surge – a _________________ of
water directly underneath the
__________________ of the hurricane
which can cause severe flooding as the storm
hits landfall.
Assignment
• Analyzing Severe Weather Data
• Observing Wind Patterns
Severe Storms (Honors)
Classified under severe storms are _____________________________________________________________
Thunderstorms
• Thunderstorm – ____________________________________
_______________________________________________
– What sizes can thunderstorms be? __________________
____________________________________________
• Development of thunderstorms involve 3 stages.
– 1st Stage: _____________________________________
____________________________________________
____________________________________________
–
–
2nd Stage: __________________________________________________________________________
_________________________________________________________________________________
3rd Stage: __________________________________________________________________________
_________________________________________________________________________________
Tornadoes
• Tornadoes – __________________________________________________
___________________________________________________________
• When do they form? ___________________________________________
• What are the stages of development for a tornado? _____________________
___________________________________________________________
___________________________________________________________
___________________________________________________________
• How is the intensity of a tornado determined? _________________________
___________________________________________________________
___________________________________________________________
Hurricanes
• Hurricane – _____________________________________
_____________________________________________
• When do hurricanes develop? _______________________
_____________________________________________
_____________________________________________
_____________________________________________
– 1st Stage ____________________________________
___________________________________________
___________________________________________
– 2nd Stage ____________________________________
___________________________________________
___________________________________________
– 3rd Stage ____________________________________
___________________________________________
___________________________________________
• How is the intensity of a hurricane measured? ___________
_____________________________________________
_____________________________________________
_____________________________________________
•
•
•
•
Eye – _____________________________
_________________________________
_________________________________
Eye Wall – _________________________
_________________________________
_________________________________
Rain Bands – ________________________
_________________________________
_________________________________
Storm Surge – _______________________
_________________________________
_________________________________
_________________________________
Assignment
• Analyzing Severe Weather Data
• Observing Wind Patterns
Classroom Hygrometer Lab
Background
Humidity is a measure of the amount of water vapor present in the air at any given temperature. The
amount of water vapor present in the air is directly related to the temperature. The higher the temperature,
the more water vapor can be suspended in the air. However, it also depends on the amount available water to
be moved in the air. In warmer climates, the air is able to hold more water vapor which often leads to a more
humid environment. Pinecones are natural hydrometers. You can often tell how humid it is by looking at
pinecones. When air is dry, pinecones open their scales to disperse seeds. In high humidity or rain, they close
them to protect the seeds. In this activity, you will use pinecones to model a hygrometer, a device that
measures the moisture content of air.
Procedure
1. Write the experimental question and hypothesis. Identify the variables used in the experiment.
2. Obtain 3 – 2 liter bottles with lids per group.
3. Cut off the top third of the each and remove any label still on the bottle.
4. In 2 of the bottles, place ¼ cup of water in the bottom. Leave the 3 rd bottle empty.
5. Tape a thermometer to the inside of each bottle with clear tape.
6. Attach a string to each pinecone and hang 1 pinecone from the opening of each bottle. Screw the
bottle cap on to hold the string in place.
7. Tape the bottle back together using the clear packing tape.
8. Label the bottle with your group members’ names/initials.
9. Place 1 of the bottle with water and the bottle without water under the heat lamp. Place the other
bottle with water in the cabinet.
10. Complete the initial readings on the table on the next page.
11. Leave them overnight, then check them for changes.
12. Complete the remainder of the table and answer the questions.
Name _____________________________________________ Period _______ Date ________________
Question: (What are you trying to determine with this experiment?)
___________________________________________________________________________________
___________________________________________________________________________________
Hypothesis: (What do you predict will happen?)
___________________________________________________________________________________
___________________________________________________________________________________
Variables:
1. What is your independent variable? ________________________________
2. What is your dependent variable? ________________________________
3. What is your control? ________________________________
Data/Observations:
Bottle #1
Initial Observations
Temperature
Pinecone
Bottle #2
Bottle #3
(open or closed)
Temperature
Final Observations
Pinecone
(open or closed)
Humidity
(none, low, high)
Post-Lab Questions:
1. Which jar was most humid? ________________________________
2. Which was least humid? ________________________________
3. How did the temperature affect the humidity?
_____________________________________________________________________________
_____________________________________________________________________________
4. Did the amount of liquid water in the bottle change overnight? Why or why not?
_____________________________________________________________________________
_____________________________________________________________________________
Conclusion: (Did your result match your hypothesis? Why or why not? What did you learn by completing this
lab?)