HOUSTON (Dow Jones)--Natural gas futures slipped Wednesday as economic concerns and relatively high gas inventories weighed on prices.

Natural gas for June delivery on the New York Mercantile Exchange recently traded 6.1 cents, or 1.4%, lower at $4.281 a million British thermal units. The front-month contract reached a low of $4.264/MMBtu earlier in the session.

Worries over debt problems in Europe have put pressure on crude and equity markets and are spilling over into the natural gas market. The natural gas market will sometimes take its cues from these markets, which can act as bellwethers for the economy and overall energy demand. Natural gas prices have moved about 5% higher over the past week as traders, who had bet on falling prices, bought back contracts and booked profits ahead of summer and hurricane season.

Jim Ritterbusch, president of the energy advisory firm Ritterbusch and Associates, wrote in a note to clients that the natural gas market will have more difficulty moving higher because of "increasing economic concerns that are filtering off of the weak stock market."

Natural gas inventories are also growing. U.S. natural gas inventories for the week ended May 7 stood at 2.089 trillion cubic feet--up 4.9% from last year and 18.4% above the five-year average. Inventories have swelled this year as producers ramped up drilling in prolific onshore natural gas fields known as shales and winter heating demand for gas faded. Those high levels of natural gas in storage can help ease concerns about short-lived supply interruptions or spikes in demand.

"Supply still remains strong," said Matt Smith a commodity analyst with Summit Energy in Louisville, Ky, said.

The natural gas market is moving through a period known as its shoulder season, when natural gas demand to generate electricity for air conditioners has not yet picked up. Nevertheless, weather forecasts over the next few weeks were providing some support for prices and could spur some cooling demand.

Meteorologists with the private forecasting firm MDA EarthSat Weather are predicting above-normal temperatures in the Northeast and "strong warmth" across the upper Midwest from May 24 to May 28, according to the its daily forecast.

-By Jason Womack, Dow Jones Newswires; 713-547-9201; jason.womack@dowjones.com