May natural gas is set to open 5 cents lower Thursday morning at $2.56 as traders expect that a government report will show an increase in inventories far above historical norms. Overnight oil markets rose.

The 10:30 a.m. EDT release of storage data by the Energy Information Administration (EIA) will give more insight into whether the upcoming injection season is really going to be as bountiful as expected and lay the groundwork for supply issues later in the summer and fall. Last year, 45 Bcf was injected, and the five-year average stands at 46 Bcf.

Energy Metro Desk (EMD) in its weekly survey expects a build of 88 Bcf and sees no surprises, although recent reports have been higher than industry expectations. "This year EIA has been higher than the market for an unearthly four straight weeks, so the odds should be that they come in low this week, right? Not so fast," said John Sodergreen, editor. "The 88 Bcf EMD consensus and survey index average of 87 feels about right this week. Pipe flows, outages, production, imports/exports, HDDs/CDDs and so on really do point to an EIA report right on the money."

Other estimates include IAF Advisors at 88 Bcf, Raymond James at 85 Bcf, and a Reuters survey of 22 traders and analysts that revealed an average 88 Bcf with a range of 80-100 Bcf.

Genscape's flow model expects an injection right in line with the consensus. "The Genscape composite estimate for this week's EIA storage announcement expects an 89 Bcf injection for the week ended April 17. Our model based on sample flows has an 89 Bcf injection, while the supply-demand model has an 86 Bcf injection. The S-D model is based off production last week averaging 73.4 Bcf/d; Canadian imports at 5.3 Bcf/d; LNG sendout at 0.1 Bcf/d; Lower 48 Demand at 64.1 Bcf/d; and Mexican exports at 2.4 Bcf/d," the company said in a report.

Next week's storage figures are not likely to get much of a boost from unexpected heating requirements. The National Weather Service forecasts that for the week ended April 25, New England is expected to endure 110 heating degree days (HDD) or 10 fewer than normal, and the Mid-Atlantic should see 102 HDD or two more than its normal seasonal tally. The greater Midwest from Ohio to Wisconsin is expected to experience 110 HDD or seven more than normal.

The early read for next week's storage report is for a build of 80 Bcf, according to Reuters. The early sample had a range of 74 Bcf to 94 Bcf and would compare to 77 Bcf a year ago and a five-year average of 55 Bcf.

In overnight Globex trading June crude oil rose 18 cents to $56.34/bbl and June RBOB gasoline added 2 cents to $1.9581/gal.