• Atmospheric instability is essential in thunderstorm development.
• The majority of thunderstorms are non-severe multicell that consist of a series of cells or several coexisting cells.
• Convective instability is often associated with a cap which suppresses weaker convection. Thunderstorms that penetrate the cap tend to be explosive.
• To destroy the cap there needs to be dynamic lifting, surface heating or a combination of both.
• The idea of the CCL uses the ability of the sun to heat the surface of the earth. Most thunderstorms that result from this kind of heating form in the afternoon when the temperature is the greatest. The CCL implies that if the ground could be heated sufficiently, to what is known as the convection temperature, upon ascent, the air would cool dry adiabatically. Convection would be start at the CCL. Keep in mind that mixing ratio is conserved.
• Low-level moisture on a low-level jet is a good indicator of potential convective activity. A low-level jet from the Gulf of Mexico is ideal for thunderstorm formation.
• Lift needs to exist, preferably on the synoptic and mesoscale, by means of surface convergence/upper air divergence (which occur simultaneously due to the law of mass continuity). Fronts, outflow boundaires, vort maxima/short waves, jet streaks and drylines are just some of the features that may exist that provide lift.
• Positive vorticity advected from the trough of an upper-level wave can indicate the presence of "good dynamics", since PVA (Positive Vorticity Advection) at 500 mb usually implies upward moving air and synoptic scale destabilization. Increased wind speed increase shear.
• The greater the amount of wind shear, the greater the chance for severe convection. This is true only if the instability is sufficient to prevent the storm from shearing apart. Wind shear can be when the winds increase in speed or change direction (veer) with height.
• Determination of the three types of thunderstorms comes primarily from the wind profile in conjunction with the amount of the instability of the atmosphere.

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