The US Geological Survey reported a 3.5 magnitude earthquake 10 miles north northwest of Valentine at 2:11 am Saturday morning. This is the first reported earthquake near the Valentine area in approximately 3 years, but the Stapleton, Arnold and Broken Bow area have reported 11 earthquakes in the last 30 days. Earthquakes are measured on a scale from 1-10, with 3.5 showing that it was felt in scattered locations outdoors and noticed by many people in buildings, but there is generally no likelihood of damage to buildings.
The public can report their findings here:
https://earthquake.usgs.gov/earthquakes/eventpage/us2000gahm#tellus