Dave Weaver / AP
Flames from the Fairfield Creek Fire are seen Monday near Springview, Neb.
More federal firefighters were being deployed to bone-dry Nebraska, where a huge wildfire is threatening more structures and two smaller fires are still out of control.
The handful of people living in Sparks, a gateway to canoeing and tubing on the Niobrara River, were on alert for possible evacuation. A 14-mile stretch of the valley already has been evacuated.
While a cold front is expected to provide some relief, highs Wednesday will still be in the mid-90s. The front may also bring some rain, but major storms aren't likely to develop near the fire. Plus, storms could also bring lightning and spark new fires.
Nebraska, like the rest of the central U.S., is suffering from the worst drought since 1956. Other signs of the stress include the fact that water levels at Nebraska's largest body of water, Lake McConaughy, are down 20 feet from this time last year, NBC affiliate KETV reported.
Hot, windy weather on Monday helped the main Fairfield Creek Fire expand to 58,000 acres, or nearly 92 square miles.
Two other smaller fires about 20 miles east of the main fire had burned more than six square miles. And Tuesday's high temperature again topped 100 degrees.
Officials estimate the fires, which have already destroyed at least 10 homes, are about 25 percent contained.
Some 200 federal firefighters were being sent to join the more than 300 crews already on the front lines.
Four helicopters are also fighting the fires, and three firefighters have been injured.
Much of the fire-swept land near the river is rugged, forested and populated with cabins, so only 17 residences had been evacuated as of Tuesday morning.
Part of the challenge is that the densely wooded ravines are difficult for firefighters to reach. And when the wind picks up, the fire can spread quickly up those ravines.
This satellite-based image shows the ravines where the main Nebraska fire is centered.
Heat and strong winds made firefighters' work difficult again by Tuesday afternoon, when temperatures had already reached 106 degrees in Valentine, which is about 20 miles west of the main wildfire. And winds continued to gust up to 25 mph.
Fire officials feel the three wildfires could be contained within a few days -- as long as more fires don't erupt.
The Associated Press contributed to this report.
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