3 reasons the Hill Fire didn’t become a monster blaze

Experts credit prevention efforts, a swift response and a lucky break with the weather for why the Hill Fire didn’t spread farther after an explosive first day that saw it burn more than 1,000 acres in a matter of hours.

That likely has residents of the mountainous rural area just east of Santa Margarita, population 1,000, breathing a sigh of relief. Recent history has shown that wildfires in the North County are capable of doing much more damage.

Last summer, the Chimney Fire near Lake Nacimiento, 50 miles away, burned more than 46,000 acres, destroyed 70 structures and took up to 4,000 firefighters 25 days to contain.

For the Hill Fire, preparation was key, Cal Fire San Luis Obispo spokesman Chris Elms said.

Cal Fire has been working that in the past few years to establish fire breaks in areas “where we have historically seen significant fire behavior,” he said.

“Some of those fire breaks helped in this situation,” he added.

The Santa Margarita itself area is no stranger to wildfires; at least five major blazes have struck the area since 1985.

A similar-sized wildfire hit the same region in 2015, when the Park Hill Fire burned 1,800 acres and destroyed two homes. It took more than 600 firefighters five days to contain.

“Over the last year we’ve been doing a lot of defensible space inspections,” Elms said.

Making a home “defensible” includes removing flammable material such as dead vegetation.

But while prevention efforts helped slow the fire down, Elms also credited the swift response by the initial incident commander, who called in all available support as soon as he realized the fire was spreading.

Within eight hours of the first report, nearly 1,000 firefighters were on scene battling it by land and air.

“The first night we were able to throw an incredible amount of resources at it,” he said.

While prevention and a rapid response helped, Elms said firefighters also were aided by “the fortune of having the weather be on our side within the first night of this thing.”

PG&E meteorologist John Lindsey said the week leading up to Monday’s fire saw temperatures in the triple digits and humidity in the single digits, setting the stage for Monday’s blaze. But starting Monday night, things began to change.

“(A marine layer) came all the way from Monterey Bay,” Lindsey said, rolling into Santa Margarita from the Salinas Valley.

Temperatures dropped, and humidity rose. As the vegetation absorbed that moisture, it became more resistant to burning.

“Having that marine layer coming in during the overnight hours probably helped the firefighters out quite a bit,” Lindsey said.

By Wednesday afternoon, Elms said the fire was approximately 75 percent contained, having burned an estimated 1,600 acres.

The weather conditions that aided the Hill Fire fight are about to change, however.

Lindsey said Thursday’s forecast high is 100 degrees, rising to 105 degrees on Friday.

“So conditions will get worse as we’re going forward,” Lindsey said, at least until the weekend.

Andrew Sheeler: 805-781-7929, @andrewsheeler

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