1. Hiding under a freeway overpass will protect me from a tornado.
Bellwork 4/29
“Two Truths & A Lie”
(Identify the lie)
Tornadoes may occur in the middle of the night and even during the winter.
Tornadoes have picked people and items up, carried them some distance and then set them down without injury or damage
Hiding under a freeway overpass will protect me from a tornado.

2. Severe weather types Tornadoes Local storm of short duration Features
Rotating column of air that extends down from a cumulonimbus cloud
Low pressures inside causes the air to rush into the center
Can have more than one vortex

3. Severe weather types Tornadoes Occurrence and development
Most frequent from April through June
Exact mechanism of tornadoes formation is not known
Basic observations show us:
1. Strong winds create horizontal rotation
2. Updrafts (associated with thunderstorm) force the rotation in a vertical position
3. Mesocyclone created & MIGHT touch down on the ground

5. Only about HALF of the mesocyclones formed become tornadoes!

6. How a Tornado Forms

7. Severe weather types Conditions for the formation of tornadoes
Occur most often along a cold front
During the spring months
Associated with huge thunderstorms called supercells
Cold cP air mixing with warm mT air
Larger the difference, larger the storm

11. Severe weather types Tornadoes Characteristics
Diameter between 150 and 600 meters (500 and 2000 feet)
Speed across landscape is about 45 kilometers (30 miles) per hour
Cut about a 10 km (6 miles) long path
Most move toward the northeast
Maximum winds range beyond 500 kilometers (310 miles) per hour
For Comparison: Category 5 Hurricane = 150mph winds

12. How do we track a tornado?
Doppler Radar
VORTEX2 projects
TOTO…(didn’t work)…Twister instrument was modeled after this

13. Measuring a Tornado Can only be measured AFTER a tornado has passed
Intensity measured by the Enhanced Fujita intensity scale
Can only be measured AFTER a tornado has passed

14. Severe weather types Tornadoes Tornado forecasting
Difficult to forecast because of their small size
Tornado watch
To alert the public to the possibility of tornadoes
Issued when the conditions are favorable
Covers 65,000 square km (25,000 square miles)

15. Severe weather types
Tornado warning is issued when a tornado is sighted or is indicated by weather radar
Use of Doppler radar helps increase the accuracy by detecting the air motion