This document discusses different types of severe weather including thunderstorms, tornadoes, hurricanes, and blizzards. It provides details on the conditions needed to form each type of severe weather, how they are measured, common warning signs, and safety precautions. Thunderstorms require moisture, unstable air, and lifting forces. Tornadoes form from rotating thunderstorms. Hurricanes need warm ocean water and form in tropical regions. Warnings help notify people when severe weather is likely or has been sighted.

2. Thunderstorms
Lightning
Tornadoes

3. Hurricanes Blizzards

4.  Weather is the state of the atmosphere in a
specific place and time
 There are many components that affect the
weather
 1. Temperature-How hot or cold the air is
 2. Humidity-The amount of water that is in the
atmosphere
 3. Air Pressure-The amount of force pressing down
on earth’s surface from the gases in the atmosphere
 4. Wind-Air moving in a specific direction

5.  An air mass is a large body of air that has
similar properties to the part of Earth’s
surface over which it develops
 What type of air mass would develop over Africa?
 What type of air mass would develop over
Antarctica?
 A boundary between two air masses of
different moisture or temperature is a front.

6.  Weather that may cause property damage or
loss of life
 Types of severe weather are:
 Thunderstorms
 Tornadoes
 Hurricanes
 Blizzards
 Floods

7.  A heavy storm that is accompanied by
rain, thunder, lightning and strong winds.
 To create a thunderstorm you need
 Moisture: cloud formation & rain
 Unstable air: relatively warm air rises
rapidly
 Lifting: from sea breezes and mountain
interaction
Thunderstorms are measured based on
their wind speeds.

8.  A Severe Thunderstorm Watch can be issued
by the National Weather Service station
 This type of storm has winds of at least 58 mph or
hail at least ¾ inch in diameter
 A Severe Thunderstorm Warning is issued
when a severe thunderstorm has actually
been observed

11.  Go inside and stay away from windows,
doors, and porches
 Stay away from trees and out of boats
 Avoid plumbing fixtures and contact with
electrical fixtures
 Stay off the phone!

13.  A destructive rotating column of air with very
high winds and a funnel shaped cloud in contact
with the surface of the earth
 Tornadoes form when a thunderstorm meets
horizontal winds which cause it to rotate.
 Tornadoes can come one at a time or in clusters
 They can also vary in size, length, width,
direction of travel, and speed

14.  Tornadoes are measured based on their wind
speeds and by using the Enhanced Fujita
Scale
EF 0 65 to 85 MPH
EF 1 86 to 110 MPH
EF 2 111 to 135 MPH
EF 3 136 to 165 MPH
EF 4 166 to 200 MPH
EF 5 Over 200 MPH

18.  Tornado Watch: weather conditions are
likely for tornadoes to form in our area
 Tornado Warning: A tornado has been
sighted in our area

20.  Tornadoes can occur in any state and any time of
year
 They typically occur from March to August
 The most common tornadoes are in “Tornado
Alley”
 “Tornado Alley” - Arkansas, Iowa, Kansas,
Louisiana, Minnesota, North Dakota, Ohio,
Oklahoma, South Dakota, and Texas

21.  Seek shelter immediately when a tornado
warning is issued
 Underground shelter is best
 If not available, find an inside room, hallway, or
closet on the lowest floor and away from windows
 Listen to the radio or watch TV for updates
on the storm

23.  A severe storm that develops over tropical
oceans and whose winds are stronger that 120
km/hr that spiral in to an intense low pressure
center
 Hurricanes begin when warm moist air over the
ocean rises rapidly
 When moisture in this rising air condenses a
large amount of heat is released
 The released heat increases the force of the
rising air

24.  They form when they gather heat and energy
through contact with warm ocean waters
 Water evaporates from the water and the
moisture produces a storm
 They can also form when a wind pattern
occurs near the surface of the ocean and
spirals inward

25.  Measured using the Safir-Simpson Scale
 3 factors are considered
 Wind Speed
 Central Pressure
 Storm Surge

26.  Hurricanes can occur during any time of the
year
 Hurricane season is from June 1st
to
November 30th
 They can form in the Atlantic Ocean,
Caribbean Sea, Gulf of Mexico, and in the
eastern Pacific Ocean

30.  Know if the location you are in is a safe zone
or whether evacuation may be needed
 Protect windows and glass with plywood
 Turn off utilities
 Have a supply kit including first aid, water,
canned goods, battery powered radio,
blankets, etc.
 After evacuation, do not return until it has
been declared safe

31.  A Hurricane Watch occurs when a hurricane is
possible within 36 hours
 The storm is being tracked to predict where it may
hit
 A Hurricane Warning is issued when it the
storm is expected to hit within 24 hours
 Evacuation may be needed

32. Two sources of
forecasting weather
 Data collected from
upper atmosphere
 Data collected on the
Earth’s surface