Final answer:
A specific purpose statement for a process speech is "To inform my audience how a thunderstorm forms," specifying the informative nature of the speech aimed at explaining the process of a thunderstorm's formation.
Step-by-step explanation:
An example of a specific purpose statement for a process speech is "To inform my audience how a thunderstorm forms." This statement clearly indicates that the speaker aims to provide information about the process and formation of a thunderstorm to their audience, which aligns with the definition of an informative speech. This type of speech is designed to explain, describe, or demonstrate a particular topic to make it understandable to the audience, utilizing various media to support the explanation.