LINCOLN, Neb. (AP) - National Weather Service meteorologist Chris Buttler said low humidity and high temperatures have created a "near critical" risk for more fires in the same areas that saw more than 50,000 acres scorched last week. The weather service in North Platte has issued a red flag fire warning for west-central Nebraska until midnight Tuesday. The affected region includes all or parts of 25 counties.

Buttler said the region missed its usual rainfall in May, June and July - the wettest summer months of the year - and the best chance to "green up" the prairie grasses and make them more fire resistant.

"It's not like eastern Nebraska, where you have a lot of corn fields and irrigated acres that are green," Buttler said. "You get a lightning strike in a cornfield, and not much is going to happen. You get lightning in a range pasture that's brown, and you're going to have problems."

The area recently endured a streak of 25 consecutive days with temperatures above 90 degrees, the longest stretch since the Dust Bowl in 1936. Though Friday broke the streak with a high below 90 degrees, Buttler said temperatures expected to hover near triple digits for at least the next several days.

Buttler said officials were most concerned about a weak cool front forecast for Monday evening that would lead to dry lightning storms. Often, he said, clouds coming off the Rocky Mountains are too high in the atmosphere and the much-needed rain evaporates before it reaches the ground.

Weather officials issue the red flag warnings to advise firefighters about conditions of low humidity, high winds and the chance of dry lightning.

"I can't put an exact number on how many we've issued this year," Buttler said. "But the number is way above what we normally issue in the summer time."

Nebraska Emergency Management Agency spokeswoman Jodie Fawl said authorities over the weekend contained six wildfires near Lake McConaughy, the state's largest reservoir and a popular summer getaway. None of the most recent fires Nebraska appears to have damaged any homes, farm buildings or other structures, she said.

Fawl said two Black Hawk Helicopters and a satellite-equipped mobile response center dispatched by state officials have since returned to Lincoln.

Buttler said the dry lightning threat was expected to diminish overnight as the humidity rises, but conditions were expected to remain dry through most of the week. The region could see rain on Friday or Saturday, he said.

Overall, he said, conditions are on the pace to be worse than drought conditions that began in the early 2000s and lasted for several years.

"In 2002, we had some rain in May and early June, and then it completely shut off," Buttler said. "This year, we haven't had anything appreciable since April. And it's killing us."

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