Update, 9:22 p.m.
Cal Fire reports the blaze is 2.8 acres and 60 percent contained.
"Due to extremely steep terrain and heavy vegetation, fire originally appeared much larger," Cal Fire said.
Crews will remain on scene mopping up for about two more hours.
Update, 8:50 p.m.
Forward progress on the fire east of Nipomo has been stopped, Cal Fire reported.
Crews from the Los Padres National Forest, Santa Barbara County and the Santa Maria Fire Department are assisting Cal Fire.
Firefighters are responding to a 20-acre vegetation fire east of Nipomo, according to Cal Fire.
Cal Fire first reported the blaze about 6:30 p.m. Thursday, initially saying the fire was in the 4900 block of Huasna Townsite Road.
About 25 minutes later, Cal Fire updated the location to the 10000 block of Crystal Springs Road.
Firefighters were reportedly making good progress on the fire, Cal Fire said.
This story will be update as more information becomes available.