The quake struck around 7:28 a.m. at a depth of nearly six miles. It originally registered as a 5.1, but was quickly downgraded.
A 2.8 aftershock hit just a few minutes later.
How to make your own earthquake kit
The shaking was felt up to 60 miles away across Southern California. People reported feeling shaking as far away as Riverside and Newport Beach.
No reports of injuries or damage have been reported.
Seismologist Dr. Lucy Jones said the region has been having more earthquakes recently.
"Whether it's statistically significant is difficult to tell," Dr. Jones said.
She added that the region has had more than an average number of 4.0 magnitude earthquakes. A 4.4 magnitude earthquake jolted Southern California last month. The average is about eight a year, but Southern California has seen 14. The previous high was 13.
Jones also added that the earthquake was not related to the weather.
"Notice these numbers are small, however. So yes, we are feeling it but it's not yet statistically significant."
"Seismologists look for patterns. Everybody looks for patterns. That's why we have myths of earthquake weather and animals. All these things are us trying to form a pattern in what is inherently a random distribution," Jones added.
DEVELOPING: We will add more details to this report as they become available.