Developing analysis · Record 012
Grade Fire,
Cuesta Grade.
A dated record of the 23 September wildfire along northbound Highway 101 in San Luis Obispo County, including evacuation history, rapid resource growth and an official-source acreage discrepancy.
Latest reviewed snapshot.
CAL FIRE’s active incident information reviewed on 24 September shows the Grade Fire at 33 acres and 27% containment. The incident began on 23 September on northbound Highway 101 in the middle of Cuesta Grade, San Luis Obispo County.
Containment rose quickly during the first evening.
CAL FIRE listed evacuation order LPF-004 and 75 personnel, including nine engines, one helicopter, two dozers and one hand crew.
The response had expanded to 130 personnel, 15 engines, three helicopters and three dozers.
Containment increased again while the reviewed acreage remained 33 acres.
Evacuation, forward progress and Highway 101.
The 3:54 PM CAL FIRE update listed evacuation order LPF-004. Local reporting later that afternoon said the evacuation order had been lifted and that forward progress had been stopped while containment continued to increase.
Those are dated milestones, not a live road-status or evacuation service. Check current CAL FIRE, CHP and transportation information before travel.
What does “forward progress stopped” mean? → · Evacuation warning vs order →
What caused the Grade Fire?
CAL FIRE continues to list the cause as under investigation. Local reporting has linked the incident to a vehicle fire along Highway 101, but Tecnobosque will keep the official cause status unchanged until the responsible agency publishes a determination.
What remains unknown.
The final cause, the reason for the 33-versus-40-acre publishing difference, the final containment trajectory and the full sequence of evacuation changes remain unresolved in the reviewed record.
Official sources.
- CAL FIRE Grade Fire page ↗
- CAL FIRE 3:54 PM update ↗
- CAL FIRE 5:48 PM update ↗
- CAL FIRE 6:05 PM update ↗
Version 1 · reviewed 24 September 2026.