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Episode 2018-21 - Tornadoes Part 1

Hello and welcome to the next edition of the Mike Wills Podcast! This is the Dog Days of Podcasting edition for August 21, 2018 where I am taking you through some of the basics of weather, storms, and radar.

{Local weather update}


  • Definition: A violently rotating column of air touching the ground, usually attached to the base of a thunderstorm.
  • Visual Clues of Tornado Formation
    • Large rounded rain-free base which could indicate a mesocyclone
    • Increasing spin in wall cloud and cloud base around the wall cloud
    • Clearing skies working into the rain-free base, which suggests a hook echo
    • Rapid vertical motions rising into wall cloud and a sinking motion around the wall cloud
    • Local burst of heavy rain just west of southwest of the wall cloud. This can sometimes be a precursor to a tornado.
  • Stages of the tornado
    • Developing Stage
      • Tornados can develop from either the ground upward or from the middle and low levels downward
      • Rear-flank downdraft and precipitation southwest of a call cloud may signal processes that help develop a tornado
      • Some circulations start in the low levels near the cloud base with the rapid acceleration of cloud material into an area of tightening rotation.
      • The first sign of tornado development may be a dust swirl on the ground. Watch this to see if it's connected to the cloud base.
    • Mature Stage
      • This is potentially the most dangerous stage of the tornado's lifetime
      • Funnel is nearly vertical
      • A visible funnel may not extend all the way to the ground or may become hidden in the wrapping precipitation
      • The rear-flank downdraft will usually wrap around the south and east sides of the wall cloud cutting off the original air flow.
      • Rain-free base may take on the horseshoe-shaped appearance. The tornado and wall cloud may be found at the north end of this structure.
    • Dissipating Stage
      • At this point, the rear-flank downdraft has wrapped around the tornado
      • The tornado will start separating from the warn buoyant air that it needs to survive.
      • The tornado will shrink, tilt, and take on a snakelike appearance before finally dissipating. This is sometimes known as the rope stage.
      • It can still be dangerous at this stage.
    • Cyclic Supercells
      • There some supercells where the inflow will be refocused a few miles east of the dissipating tornado.
      • If the environment is favorable, a new mesocyclone and wall cloud will form. This can become a new tornado.
      • Always check overhead when you are near the inflow region of the supercell.
  • Tornado Strengths
    • It is measured by the enhanced fujita scale
    • EF 0 = 65-85mph winds
    • EF 1 = 86-110mph winds
    • EF 2 = 111-135mph winds
    • EF 3 = 136-165mph winds
    • EF 4 = 166-200mph winds
    • EF 5 = 200+mph winds

Link/Picture of the Show


Wrap Up

Thank you for listening and remember to always watch the clouds and be weather aware.

Contact Information

podcast/ddop/public/episode_201821.txt · Last modified: 2018/11/22 14:30 (external edit)