We all hear the terms when there's a threat of severe weather. But what does each alert mean, and how does it affect you?

The severe weather outlook for Saturday is shown above. A Level 4 out of 5 severe weather risk has been added and now expanded for Saturday in the areas in red, which is very unusual this far in advance. The rest of the state will have a Level 3 risk on Saturday. Storm Prediction Center

It marks only the third time since at least 2006 that the highest risk level has been issued the day before an expected outbreak.