NAPA COUNTY, Calif. (KGO) -- Weather conditions and visibility were helping firefighters attack the Glass Fire from the air in Napa County Saturday.
"This is really too close for comfort but it's hard to leave," said Xitlaly Vasquez.
Vasquez was getting stressed watching the Glass Fire move closer to her home outside Calistoga on Highway 29.
She had the sprinkler going and a generator cranking. Thousands have been evacuated in the area, but Xitlaly isn't leaving yet.
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"It's about two miles away, we're aware, we were told to evacuate two days ago but we're ready to go if we need to," said Vasquez.
The Glass Fire is still on the move, flames were erupting over a ridge as the fire made a slow smoky push towards Lake County.
There was better news for firefighters Saturday, air quality and visibility improved. But by 4pm, the National Weather Service Bay Area reissued a Red Flag Warning for the North Bay mountains effective through 6 a.m. Sunday.
CAL FIRE Public Information Officer Jason Shanely said a hotspot broke out near Highway 29, north of St. Helena around 4:30 p.m.
"Very indicative of the winds and the changing of the wind direction as the time progresses during the day. These things move really really fast. It got big really fast," Shanley said.
He said embers can travel half a mile or a mile away.
"When you have high heat and low humidity, fuels are already dry, and then you have the fires that are spotting, and sending embers and an ember can start something and before you know you have another 500 acres on your hands," Shanley said.
By Bale Grist Mill State Park, fire crews made their way up the hill to attack the fire by foot. One fire official said they don't need fire engines where the hotspot it, they need people.
"So think about that, this fire is not the only thing affected by Red Flag Warnings. The firefighters also, it takes a toll on their body," Shanley said.
Shanley said some of the fire crews have been away from home since mid-July traveling from fire to fire.
Shanley is based out of San Diego and he came from the Castle Fire before this.
A Cathedral City firefighter told us this is his 15th straight day working.
"So for them to be able to stay this dedicated for this long, and to be doing this good of a job, hats off to them," Shanley said.
The entire city of Calistoga remains under an evacuation order. Shanley said he's aware residents are anxious to return but he asks them to be patient.
"We're doing the best that we can to prioritize you getting back to your home, but just understand there's just so much going on right now. The last thing we would want to do is put a resident in harms way," Shanley said.
By nightfall the winds were calmer than they were at four in the afternoon. Fire crews lit a back burn not far from Bale Grist Mill, a historic landmark.
ABC7's Cornell Barnard saw air tankers make drop, after drop of retardant, about a dozen air runs in less than 90 minutes.
"We got clean air, we are doing drops with fixed wing aircraft all day," said CAL FIRE Battalion Chief Mark Brunton.
Timelapse video of the fire from Mt. St. Helena showed smoke and flames for hours.
Gusty winds and extreme heat are still challenging hundreds of firefighters on the ground.
But air resources are a big relief to homeowners like Xitlaly, who has a front row seat to the firefight.
"It's an amazing job they're doing but when it comes to your home, it's a different story, cool show though," Vasquez added.
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