![Firefighters work against the advancing Post Fire on Sunday.](https://ca-times.brightspotcdn.com/dims4/default/1590226/2147483647/strip/true/crop/4500x2999+0+0/resize/2000x1333!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2F84%2F90%2F057ecfa34857861335dab308fef6%2Fcalifornia-wildfire-31169.jpg)
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A wind-driven wildfire along Interstate 5 near the Grapevine exploded to more than 12,000 acres by early Sunday and had charted a path south toward the town of Castaic, prompting evacuations throughout the area, officials said. The Post fire, which originated Saturday in Gorman in northwestern Los Angeles County, was only 2% contained Sunday afternoon as high winds, low humidity and steep terrain hampered firefighting efforts.
Meanwhile, firefighters were battling another brush fire in the San Bernardino County community of Hesperia that broke out after 6 p.m. Saturday in the 18000 block of North Highway 173. That fire has burned more than 1,300 acres and was 20% contained.
The Post Fire
![Fire crews battle a hot spot on Orwin road.](https://ca-times.brightspotcdn.com/dims4/default/7fa61d2/2147483647/strip/true/crop/5075x3383+0+0/resize/2000x1333!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2Fb9%2Faf%2F3eda405e411896b5e098ba5c473a%2F1461744-me-post-fire-gorman-jja-0005.jpg)
Fire crews battle a hot spot on Orwin road.
![A water dropping helicopter fills it's tank as efforts to fight the Post Fire continue.](https://ca-times.brightspotcdn.com/dims4/default/65e830b/2147483647/strip/true/crop/5496x3664+0+0/resize/2000x1333!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2F7a%2Fea%2F0dc496d145afbc06099023e6e0c6%2F1461638-me-0616-post-fire-7-rcg.jpg)
A water dropping helicopter fills it’s tank as efforts to fight the Post Fire continue.
![Fire crews battle a hot spot at the Gorman Brush Fire in northern Los Angeles County on Sunday.](https://ca-times.brightspotcdn.com/dims4/default/d7d2f98/2147483647/strip/true/crop/4859x3239+0+0/resize/2000x1333!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2Ffa%2F70%2Fba5870724ffcaf33db59afbbffd6%2F1461744-me-post-fire-gorman-jja-0018.jpg)
Fire crews battle a hot spot.
![Fire crews keep an eye on flames from a burn out operation.](https://ca-times.brightspotcdn.com/dims4/default/d0efd92/2147483647/strip/true/crop/3467x2311+0+0/resize/2000x1333!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2F4a%2F1b%2F6a3791c744ad8a5816dbee7120f9%2F1461638-me-0616-post-fire-1-rcg.jpg)
Crews conduct a burn-out operation Sunday near Hungry Valley Road.
![Crew members of the Little Tujunga Hot Shots work to control flames.](https://ca-times.brightspotcdn.com/dims4/default/54f54ac/2147483647/strip/true/crop/3744x2496+0+0/resize/2000x1333!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2F99%2F23%2F031e05ab408d95227f781ee22207%2F1461638-me-0616-post-fire-2-rcg.jpg)
Members of the Little Tujunga Hot Shots at work.
![Firefighters at work in Gorman.](https://ca-times.brightspotcdn.com/dims4/default/16a364e/2147483647/strip/true/crop/4500x3000+0+0/resize/2000x1333!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2Ffa%2F1f%2F308adb554d2fb99bddf3e285def4%2Fcalifornia-wildfire-51130.jpg)
Firefighters at work in Gorman.
![The Post fire advances on structures in Gorman.](https://ca-times.brightspotcdn.com/dims4/default/00f739d/2147483647/strip/true/crop/4500x3000+0+0/resize/2000x1333!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2Faa%2F91%2F27aead0040f4b1d2d1fce35308b0%2Fcalifornia-wildfire-24584.jpg)
The Post fire advances on structures in Gorman.
![Firefighters work against the advancing Post Fire on Saturday.](https://ca-times.brightspotcdn.com/dims4/default/752a237/2147483647/strip/true/crop/4269x2846+0+0/resize/2000x1333!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2Fe7%2F21%2Fa1134cb34ca6ad14060192989f89%2Fcalifornia-wildfire-15007.jpg)
As the fire spreads, experts are gauging the severity of this year’s fire season. A wet winter has nurtured a potentially heavy fuel load of thick grasses, which are drying as temperatures rise.
![Firefighters work under a smoldering hillside left behind by the Post Fire](https://ca-times.brightspotcdn.com/dims4/default/65f4914/2147483647/strip/true/crop/3936x2632+0+0/resize/2000x1337!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2F90%2F70%2F0fca334d4c6fb5e797ee6bab14f8%2Faptopix-california-wildfire-59063.jpg)
A smoldering hillside is left behind by the Post fire.
The Lisa Fire
![CalFire drops water from a helicopter to battle the wind driven Lisa fire from the air.](https://ca-times.brightspotcdn.com/dims4/default/793f7f9/2147483647/strip/true/crop/4817x3158+0+0/resize/2000x1311!/quality/75/?url=https%3A%2F%2Fcalifornia-times-brightspot.s3.amazonaws.com%2F60%2Fa0%2Fc4c826ac452c9d94d3215734c6c3%2F1461720-me-lisa-fire-4-gmf.jpg)
CalFire drops water from a helicopter to battle the wind driven Lisa fire from the air in a canyon east of Moreno Valley on Sunday in Beaumont. As of 6:45pm the fire had burned 867 acres.
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