July natural gas is expected to open 4 cents lower Thursday morning at $2.81 as traders digest healthy estimates of government storage data but note greater risk to the forecast than normal. Overnight oil markets were mixed.

Bears will be looking for a chance to drive a stake in the heart of the bullish case Thursday morning with the 10:30 a.m. EDT release of Energy Information Administration (EIA) inventory data. The market has yet to be convinced that the upcoming injection season will not see abundant, if not burdensome, supplies once storage builds end by Oct. 31. For the moment, estimates show that injections will have a tough time equaling those of last year, although matching the five-year pace looks less challenging. Last year at this time, 113 Bcf was injected, and the five-year rate is for a 95 Bcf increase.

Estimates are varied. IAF Advisors calculates a build of 105 Bcf, and Ritterbusch and Associates figures on a 102 Bcf increase. A Reuters survey of 21 traders and analysts showed an average of 99 Bcf with a range of 87-107 Bcf.

Others see a risk that the number might be higher than estimates. Energy Metro Desk (EMD) in its weekly survey said, "The spread between the three categories we track [surveys, banks, individuals] is wide at 3.8 Bcf and thus signaling a surprise of 5 Bcf higher or lower than the market. All indications point to a build bigger than this week's survey index of 99 Bcf. This week, we note that our EMD consensus was 2.5 Bcf higher than the survey index -- higher bias is the word."

John Sodergreen, EMD editor, estimated 100 Bcf for last week's number and came in way off the 92 Bcf actual figure. Sodergreen is calling for a 100 Bcf build this week and said, "Last week the 100 forecast was way off; this week, it should be close to spot on."

In overnight Globex trading July crude oil eased 9 cents to $57.42/bbl and July RBOB gasoline rose a penny to $1.9460/gal.