There is no proven way to predict an earthquake. Geologists are working to develop an early warning system, but there is still much to be learned about what happens just before an earthquake hits. Part of the problem is that earthquakes don't always behave in a consistent way—some signs occur at different times (days, weeks, or seconds before the event), whereas sometimes those signs do not occur at all. Read on to learn possible signs of an earthquake, and how to be prepared should you experience an earthquake.