July natural gas is expected to open unchanged Thursday morning at $2.63 as traders anticipate a plump triple-digit increase in working gas inventories. Overnight oil markets eased.

Analysts are calling for a series of several triple-digit increases to working gas inventories for the next several weeks, and Thursday’s 10:30 a.m. EDT report by the Energy Information Administration (EIA) may give clues as to just how large an influx might ultimately be expected. Estimates are in the 125 Bcf area, but a build significantly higher could cast a more bearish pall over much of the injection season.

Last year, a stout 118 Bcf was injected, and the five-year average is for a more modest 92 Bcf. By most accounts, this week’s build report should surpass even the husky increase of last year. Tradition Energy estimates a 121 Bcf increase, and United ICAP is calculating a 126 Bcf build. A Reuters survey of 25 industry cognoscenti revealed an average 121 Bcf also, with a range of 101 Bcf to 130 Bcf. Bentek Energy estimates a 125 Bcf gain.

Observers note that the week contains something of a wild card with the Memorial Day weekend, which will typically lessen demand and encourage greater injections. This raises the possibility of upside risk to forecasts, but it also limits the downside. Bentek said the last five years have exhibited this trend, with the actual EIA figure surpassing Bentek’s estimate.

Gas buyers across PJM seeking to procure supplies for power generation may have their work cut out for them as little help can be expected from wind generation. WSI Corp. in a morning forecast said, “Light and variable wind generation is expected into the weekend. Output may occasionally top out in excess of 1 GW, [and] the expected frontal system may provide a boost to wind gen during Sunday into Monday.

WSI predicts that “a slow-moving and complex storm system along and off the East Coast will continue to promote mostly cloudy skies, occasional light rain, drizzle and a northeast flow across the Mid Atlantic during the next one to two days. This will lead to below-average temperatures with highs in the 60s and 70s. Partly cloudy skies and seasonable conditions are expected across western PJM. Eventually, a weak cold front may slide across the power pool late.”

In overnight Globex trading July crude oil fell 34 cents to $59.30/bbl and July RBOB gasoline slipped a penny to $2.0370/gal.