>> back in this country to a big story we are following tonight. that out-of-control wildfire in yosemite national park . now one of the biggest in california history . it is the size of chicago. so big they can see it on the international space station , the image nasa provided us. nbc's tom costello joins us with the latest. tom, good evening.
>> reporter: hi, lester. that's the smoke behind me off the top of the trees and also the building there. the fire service fire chief tells me this is the toughest fire he has fought in his 30-year career. sunrise this morning in tuolumne, california, brought relief. the town was still standing. the fire over the ridge and in the river canyons below stretches some 200 square miles including yosemite national park . commanders think they're starting to get the upper hand, but it is only 15% contained. we are facing record fuel, dry conditions across this state.
>> the fire shot over here.
>> reporter: tucked between the trees on robin hood way we found strike team 2276 alpha, from san mateo county . if the fire comes over the hill it will be on top of them and the homes they're prepared to defend within minutes.
>> this is really dangerous. it is dangerous. we have had 19 firefighters, hot shot crew, die just recently in arizona. fire is unpredictable. when it gets in the tree tops it moves different than it does on the ground.
>> reporter: the challenge -- fires this big create their own wind patterns and vacuums. in yosemite national park the fire remains contained in a remote wilderness area . it has got wildlife, like this mother and cub on the move. but for the city of san francisco , some 150 miles away , the concern is the water supply . most of which comes from the hetch hetchy reservoir in the fire zone.
>> when you burn down everything you have a moonscape out there that with floods can contaminate the waters.
>> oh, man.
>> reporter: just outside of yosemite national park today, 80-year-old louis peyton returned to the family cabin his father built.
>> this was the main cabin here.
>> reporter: all of it gone.
>> we're going to do our best to get it back, you know? for our grandkids. [ indiscernible ]
>> reporter: meanwhile across this region, whole towns have turned out to thank the thousand of firefighters who have come from as far away as san diego and the oregon state line. the fight continues.
>> somebody has got to put this fire out. unless it starts to rain we have to fight this thing aggressively.
>> reporter: fire commanders think they're making good progress on this fire. but the afternoon winds, big variable and they're kicking up yet again. lester.
