TORDANOES

CAUSES OF TORNADOES

• Tornado conditions are caused when different temperatures & humidity meet
• To form thunderclouds. In the U.S warm, wet winds from the Gulf of Mexico move
• Northward in spring &. Summer, meeting colder,dry Canadian winds moving southward

F-0

• 65-85 mph
• Causes light damage
• Breaks branches off trees and pushes over small trees

F-1

• 86-110 mph winds
• Causes moderate damage
• Tiles come off of roofs, cars and trailers get pushed

F-2

• 111-135 mph winds
• Causes considerable damage
• Roofs get torn off. Big trees get toppled. Mobile homes are destroyed

F-3

• 136-165 mph wind speed
• Causes severe damage
• Trains are over turned

F-4

• 166-200 mph winds
• Causes catastrophic damage
• Well constructed structures are leveled

F-5

• 200+ mph winds
• Causes total damage
• Cars become missing.

TORNADO ALLEY

• North Texas up through South Dakota

ENVIRONMENTAL EFFECTS OF TORNADOES

• Tears down electrical poles that causes fires
• Up-roots and kills trees
• Kill animals and effects the food chain

MOST DESTRUCTIVE TORNADO IN THE US HISTORY

• Tri-State tornado, went through Missouri,Illinois, and Indiana
• On March 18.1925, it was likely an F5 but they couldn't record
• Tornadoes like we can today. Holds the longest path length of 219 mi
• Lasted about 3.5 hours. Fastest forward speed for a tornado at 73 mph

LOCAL TORNADO

• Waco tornado of 1953
• F5 on the Fujita scale
• 114 people killed, 597 injured
• $50 million in property damage

TORNADO SEASON

• Runs through the spring months. Mostly in April and July
• May and June are the worst months for tornadoes
• Low-level heat, moisture, and instability necessary for tornado formation