USA Today
Usa Today: Rising Air Creates Spring, Summer Ice
This article gives you basic information on hail. There are links at the bottom of the page to how hail forms, how updrafts breed hail and thunderstorms.
University Corporation for Atmospheric Research
Ucar: Weather Fronts
When a front passes over an area, it means a change in the weather. Many fronts cause weather events such as rain, thunderstorms, gusty winds and tornadoes.