Unstable weather and cloud-to-ground lightning across Big Sur prompted crews battling the massive Timber Fire to pull back from active fire lines and move to safer ground.
The fast-growing wildfire has shut down state parks throughout the area, while evacuation orders have forced hundreds of residents to leave as firefighters work to gain control of the flames.
According to Cal Fire, 503 structures are still under serious threat, among them some of Big Sur’s best-known luxury destinations, including Alila Ventana Big Sur and Post Ranch Inn.
U.S. Forest Service incident meteorologist Matt Mehle said Wednesday that low clouds helped keep sections of the Highway 1 coastline relatively moist, but the higher ridgelines above Big Sur remained critically dry and exposed to wind-driven fire growth.
By Thursday morning, the Timber Fire had scorched 4,245 acres and was only 7% contained. Officials were especially focused on the fire’s southern and western flanks, where scattered homes near Partington Ridge Road remain at risk.
“We actually did have upper-level moisture move over the fire, that led to showers and actually some thunderstorms,” Mehle said in a Wednesday social media update. He noted that a “pesky marine layer” continued to keep low clouds “hugging the coast,” even as the higher terrain stayed dry.
Mehle said conditions on the ridges were far different from those closer to the shoreline. “The crews that are working the fire line along Coast Ridge Road, they’re seeing very dry conditions, much different weather than the crews are seeing down on Highway One,” he said.
Fire Behavior Analyst Morgan Diefenbach cautioned that brief showers may temporarily boost humidity, but they do not eliminate the danger of thunderstorms igniting additional fires beyond the main Timber Fire perimeter.
“While relative humidity is temporarily increased over the fire area with that precipitation, lightning obviously is problematic for us because it can cause new starts outside of the existing fire perimeter… Sometimes it takes those smokes a little while to pop up or to be detected,” Diefenbach said.
The firefighters reengaged with the Timber Fire Wednesday evening amid possibilities of isolated showers and thunderstorms.
A response force of 1,405 personnel, 25 engines, and 6 helicopters are actively engaged and taking advantage of high humidity under a heavy marine layer at lower elevations, San Benito-Monterey Unit of CAL FIRE said in an update Thursday morning.
Firefighters worked overnight to successfully establish lines down to the Big Sur River on the northern side and worked down Partington Ridge toward Highway 1 on the southern end to protect nearby structures.
Highway 1 remains closed between Mile Post Marker 45.1 near Big Sur Bakery and Mile Marker 37 near Julia Pfeiffer Burns State Park.
