Fast Track Riders (https://fastrackriders.info) has WERA events in SoCal.

Here's their schedule:

May 26,27,28 - Auto Club Speedway
June 9 - Willow Springs
June 10-11 - WERA Willow SPrings
June 23,24,25 - Auto Club Speedway
June 30 - Buttonwillow
July 1-2 - WERA Buttonwillow
July 21-22 - Auto Club Speedway
July 23 - WERA Auto Club Speedway
September 15,16,17 - Auto Club Speedway
October 20,21,22 - Auto Club Speedway
November 25,26 - Auto Club Speedway
December 9,10 - Auto Club Speedway (cars only)

2019 events all at Auto Club Speedway

https://fastrackriders.info/