NEW YORK (Dow Jones)--Natural gas futures ended flat Thursday as traders weighed signs of economic recovery against mixed weather forecasts and a glut of supply.

Natural gas for December delivery on the New York Mercantile Exchange settled less than a penny lower at $5.062 a million British thermal units after reaching a high of $5.129/MMBtu earlier in the day.

Gas prices received some support from a Commerce Department report that showed U.S. gross domestic product rose at an annual rate of 3.5% in the third quarter, signaling that the recession has ended. Gas traders have closely watched economic data for signs of a recovery that would boost energy demand.

Traders were also eyeing weather forecasts to determine whether heating demand will put a dent in ample gas inventories. Commodity Weather Group, a Bethesda, Md., private forecaster, was predicting warmer-than-normal temperatures across parts of the Southeast, Mid-Atlantic and Great Lakes regions, with normal temperatures throughout the rest of the East, from Oct. 29 to Nov. 2. From Nov. 3 to Nov. 7, below-normal temperatures were expected in the Northeast and Mid-Atlantic, with above-normal temperatures across much of the Midwest.

"The market's more or less just waiting on the weather," said Allen Rather, an independent energy analyst in Victoria, Texas. "There's a lot of indecision in general today."

The gas market hardly budged on a government report of a modest injection into U.S. gas storage for the week ended Oct. 23. The U.S. Energy Information Administration reported that natural gas in U.S. storage for the week grew by 25 billion cubic feet, below the 29 bcf analysts had predicted in a Dow Jones Newswires survey and well below the five-year average of 43 bcf.

Natural gas in U.S storage for the week ended Oct. 23 stands at 3.759 trillion cubic feet - 11% higher than last year and 12.4% above the five-year average. Natural gas stockpiles are expected to approach storage capacity before winter heating demand begins to draw down those supplies. As storage facilities near capacity, pipeline pressure rises, making it difficult to add more gas.

"To the extent that this represents a lack of available storage capacity to receive more gas, this could still be seen as a bearish [EIA] report," Tim Evans, an analyst with Citi Futures Perspective in New York, wrote in a note to clients Thursday.

-By Christine Buurma, Dow Jones Newswires; 212-416-2143;