Last night at about 9:30 pm, a moderate earthquake woke us up and had us running for a doorway to stand in. It lasted perhaps 25 or 30 seconds. Being nighttime, there was little ambient noise – so the rumblings associated with the quake were quite audible. In fact, it was the noise that alerted me to the fact that there was an earthquake in progress, rather than the shaking.
The USGS web site puts the magnitude at 5.7, and the epicenter at a few miles southeast of Ocotillo.