Tornadoes

Stage 0

Mesocyclone – wind shear can cause the cloud to begin to rotate (5-10 km)

Stage 1

Wall cloud – produced from a mesocyclone

Stage 2

Dust whirl

Stage 3

organizing stage funnel extends further

Stage 4

funnel formed and touched down; Mature stage; maximum wind velocity

Weakening stage

funnel more tilted and thinner; winds decreasing

Decay stage

rope like appearance; winds can still cause damage but weakening

EF rating

EF0 – EF5

Higher the EF rating the _____ likelihood occurrence is

lower

U.S.

Most occur in spring into summer (March to July)

·       Most occur during late afternoon (4-6pm)

·       Most occur during Spring

Southeast Texas

most occur during 2-4pm

warning signs

Hail and sever weather clouds

tornadoes during any season

Southeast Texas

Is it exactly the same or have there been changes over the recent decades?

Changing overt tome seeing more tornadoes in march in recent years - same pattern but uptick in march and later into seasons / increasing amount in march / moving more east

EF ratings are categorized by

damage - greater the winds and greater the damage

More intense tornado the more ___

rare

Characteristics

• Average 300-2000 ft in diameter; largest was 2 miles (relatively narrow compared to other storms)

• Average SPEED 35 MILES PER HOUR

• Winds can range from 50-300 mph (no other storm can reach a 300mph speed, but 50 other storms can microbursts)

• Tornadoes won’t last more than a couple hours; mostly a few minutes (not as long as hurricanes or durations; but can last longer than microbursts)

Direction they move most often

SW to NE towards cyclonic low pressure system

Damage pattern

Spiral pattern of destruction on the ground; or microburst out from the center; straight line winds