Can earthquakes be predicted?

No. Scientists cannot predict exactly when and where an earthquake will happen and how large it will be. They can estimate long-term probabilities for a region, such as the chance of a magnitude 6.7 or larger in the San Francisco Bay Area over 30 years, but those forecasts are not warnings.

Prediction vs forecast vs early warning

• Prediction would give a specific date, place and magnitude. According to USGS, no scientist has ever predicted a major earthquake this way, and no reliable method is known.
• Forecasting gives probabilities over years or decades for a region, based on fault history and measured strain. This is what building codes and insurance use.
• Early warning detects an earthquake that has already started and sends alerts ahead of the slower, more damaging waves. It buys seconds, not days, and works only if you are some distance from the epicentre.

Why prediction is so hard

Faults are deep and cannot be measured directly. Earthquakes follow chaotic processes, and the signs people point to (animal behaviour, weather, radon, “earthquake lights”) have not been shown to work reliably. Because small earthquakes are common and large ones rare, it is easy to find a “success” after the fact.

What helps instead

Preparing is more reliable than prediction. Secure heavy furniture, keep water and supplies, and know the plan for your household. See our preparedness checklist.