Crews in north Texas are battling a wildfire that has so far destroyed 150 homes and scorched 60,000 hectares.

The Possum Kingdom Lake fire, west of the Dallas-Fort Worth area, is the largest of several blazes that have been burning across the drought-stricken state for the past week.

The fire started last Friday near the lakeside community and has since spread to two other counties.

Several roads near the reservoir have been closed. Boating access was declared off limits Tuesday to everyone except emergency workers responding to the wildfire.

On Tuesday, authorities ordered the 400 residents of Palo Pinto, about 80 kilometres west of Fort Worth, to head east to Mineral Wells because of the advancing flames.

Palo Pino County Sheriff Ira Mercer told CBS News that fire crews have not found a way to stop the blaze and have told him this is "the perfect storm as far as fires are concerned."

But weary firefighters had some reason for hope as rain and higher humidity levels were forecast for the rest of the week in parts of the state.

A 20 to 30 per cent chance of rain was forecast for Wednesday and Thursday in the North Texas area, said Daniel Huckaby, a forecaster at the National Weather Service in Fort Worth.

"Some areas will get some rainfall, but unfortunately most will not. And with the chaotic wind that thunderstorms can produce, and the lightning they can produce, that can make matters worse," Huckaby said. But as the humidity levels rise, "even without the rain, conditions are looking more positive."

The fire also threatens the small towns of Graford and Strawn, south of the lake, although no evacuation has been ordered.


With files from The Associated Press