Severe Convection: Mesoscale Convective Systems

Severe Convection: Mesoscale Convective Systems

After completing this lesson, you should be able to do the following things.

  • Recall the definition of an MCS
  • Recall common types of MCS organization, especially squall lines and bow echoes
  • List the potential weather hazards most likely associated with MCSs
  • Identify key features associated with MCS initiation and evolution
  • Recognize a likely MCS in radar imagery Squall Lines
  • Identify the various forms and compositions of squall lines
  • Locate key squall line structures, including the cold pool, leading gust front, and rear-inflow jet
  • Recall evolution of the surface pressure pattern during the lifetime of a squall line
  • Explain the types of squall line formation
  • Identify the phases of squall line evolution
  • Using satellite and radar imagery, recognize the type and phase of a squall line
  • Explain what determines if a squall line will be weak-to-moderate or moderate-to-strong
  • Quantify low-level shear and identify which vertical wind shear most controls squall line strength
  • Recall movement of long lines versus short lines, and movement of cells within a line
  • Identify line back building and recognize conditions which support it
  • Describe a line echo wave pattern and identify one from radar data
  • List the differences between tropical and extratropical squall lines Bow Echoes
  • Define bow echoes and identify weather patterns conducive to their development
  • Explain what a rear-inflow notch is and how to assess it with the MARC technique
  • Discuss the factors that contribute to bow echoes being an especially severe form of MCS
  • Describe the most likely time of onset and location of damaging winds from a bow echo
  • Describe the characteristics of a derecho Mesoscale Convective Complexes (MCCs)
  • Recall how MCCs are defined via satellite imagery
  • Describe where MCCs usually occur
  • List the potential weather hazards associated with MCCs
  • Explain what an MCV (or MVC) is and its relationship to an MCC
  • Recognize the signature of an MCV from satellite imagery
  • Recall why it is important to monitor an MCV MCSs and Numerical Weather Prediction (NWP)
  • List model convection issues and describe their impact on forecast elements
  • Describe the difference between a model with convective parameterization and one without
  • List the relative strengths and weaknesses of using a model with higher resolution (10 km WRF) versus one with lower resolution (22 km Eta)
  • Describe common NWP limitations and errors related to forecasting large-scale convection
  • Explain how model output should be applied to forecasting MCS occurrence