The Ferguson Fire burns near Yosemite National Park on Monday, July 16, 2018. (Sierra National Forest)
Two more firefighters have become casualties of the big wildland blaze burning just outside Yosemite National Park.
Officials said one firefighter was transported to a hospital early Wednesday to undergo surgery for a broken leg suffered while battling the Ferguson Fire. A second firefighter suffered heat-related issues and was treated and released.
Last Saturday, Braden Varney, 36, a Cal Fire heavy equipment operator, was killed when his bulldozer overturned.
The blaze, which started late Friday in Mariposa County, is moving through dry brush and timber in the Sierra National Forest, along Yosemite's western edge. As of Wednesday morning, the fire had burned across 17,319 acres -- about 27 square miles -- and was 5 percent contained.
Cal Fire says the more than 1,800 firefighters battling the blaze are facing hot, dry conditions, and the agency says fire activity is expected to intensify over the next two days.
"It's gonna start getting hotter," said Cal Fire spokesman Richard Eagan. "Hotter and drier usually isn't good for us as firefighters."
As is often the case with California's wildland fires, the terrain is difficult.
"It's pretty steep, not really easily accessible by foot," Eagan said. "So it's been challenging for the firefighters for sure."
Officials say monsoonal moisture that's expected to start pushing in from the south on Wednesday afternoon could pose another threat, with the possibility of thunderstorms that could produce gusty, erratic winds.
U.S. Forest Service spokesman Jim Mackensen said fire commanders are keeping a close eye on the weather.
"We have meteorologists here watching the weather radar, and as they see storms moving in this direction, they will alert our people on the ground, and they will disengage from the fire and move to an area of safe refuge," he said.
The blaze has forced the closure of a portion of Highway 140, one of the key routes into Yosemite. And Mackensen said there's a chance the fire could burn into the park at some point.
"It's definitely a possibility based on the terrain," Mackensen said. "The fire wants to try and travel up the south fork of the Merced River drainage, which does take it into the Wawona area [of Yosemite], and we are looking at that."
Park officials say all trails, campground, restaurants and lodges within Yosemite remain open, though smoke from the wildfire is polluting the air and limiting visibility. The smoky conditions have prompted some tourists to cut their trips short due to limited visibility at some of the park's biggest attractions.
The poor air quality also prompted air pollution officials in the San Joaquin Valley on Sunday to issue health alerts for Stanislaus, Merced, Madera, Fresno, and Tulare counties that will remain in effect for the duration of the fire.
Mandatory evacuation orders remain in effect for the communities of Cedar Lodge, Savage’s Trading Post, Jerseydale, Sweetwater Ridge, Mariposa Pines and the stretch of Incline Road between Clearing House and the Foresta Bridge.
Cal Fire's Eagan said hundreds of people showed up for a community meeting about the fire in the community of Ahwahnee on Tuesday night, and another meeting is planned for 4 p.m. on Wednesday at the El Portal Community Hall.
This post has been updated to include more information on the injured firefighters.