A low-pressure weather system is bringing instability to the Southern California region, with a chance of more rain and thunderstorms this weekend.

The National Weather Service said in a statement “there’s a good chance” that showers and storms will begin developing late this evening into Saturday morning, with the weather expected to taper off Saturday night.

The NWS gives a 30% chance of thunderstorms Friday night, a 40% chance on Saturday and a 20% chance on Sunday. Temperatures are expected to reach the low 70s.

The possibility of inclement weather led the city to cancel a World Mental Health Day Resource Fair that had been scheduled from 10 a.m. to 2 p.m. Saturday at Admiral Kidd Park.

This weekend’s storm would be the second so far since the start of the rain year on Oct. 1.

Long Beach received .11 inches of rain late Tuesday and into Wednesday after a band of thunderstorms moved through the area.