It's been my experience over many years of following severe weather events (with some college training in the field) that the following clarification of the "risk" levels needs to be made:
1. Slight Risk: Continue with your plans for the day, but be aware that severe weather will probably occur.
2. Moderate Risk: Severe weather will occur. Stay abreast of the situation and be prepared to take protective measures.
3. High Risk: Get your ass in the basement NOW and don't come out until they dig you out.
I'm glad I could clear that up.