EIA natural gas storage report: the Thursday number for NG futures

What the report measures

Natural gas is injected into underground storage when demand is low, mostly in the warmer months, and withdrawn when heating demand peaks in winter. The report estimates working gas in storage at the end of the previous week and the net change, by region: East, Midwest, Mountain, Pacific and South Central, the last split between salt caverns and non-salt facilities.

The change is compared with analysts' expectations, with the five-year average change for the same week, and with the same week a year earlier. The level against the five-year average indicates whether the market enters the next season with a surplus or a deficit.

Drivers behind the number

• Weather: heating demand in winter and power-generation demand for cooling in summer dominate week-to-week changes.
• Production: output trends set the supply side over months.
• LNG exports: feedgas to liquefaction terminals takes gas out of the domestic balance.
• Power burn: the share of electricity generated from gas depends on relative fuel prices and on wind and solar output.
• Reclassifications and revisions: EIA occasionally reclassifies volumes, which can distort a weekly change.

Why NG futures react

A smaller injection or larger withdrawal than expected suggests a tighter balance, and a larger injection or smaller withdrawal the opposite; futures reprice on the gap, weighted by where storage stands against the five-year average and by the weather outlook. Because weather forecasts change daily, the storage figure is one input among several, and a surprise can be overridden by a new forecast within hours.

Order flow in NG at 9:30 a.m. Chicago

Natural gas futures are known for fast moves and a book that can thin quickly. Ahead of the release, the inside levels on the heatmap often fade and the spread widens; at the release, the first trades can sweep several levels. The footprint of the first minutes shows whether aggressive orders keep finding new prices or run into resting size that holds.

Because the reaction mixes the storage surprise with the latest weather forecasts, a strong first move that reverses within minutes is common. Reading delta alongside price is useful: a new extreme made on shrinking delta is a sign of fading aggression, while an extreme made with delta expanding shows that aggressive orders are still arriving.

In Senzoukria

The calendar row for natural gas storage is described as “Nat gas inventory — NG driver.” when the name matches, and the Quant mode card classifies it in the Energy family with CL and NG first among the contracts concerned. With the NG preset chosen in the wire, “What moves my session” keeps the next twelve hours of US releases.

The heatmap's time span control goes from 5 seconds to 4 hours; a short span around 9:30 CT shows the liquidity withdrawal and the sweep at their real scale, and the bid/ask bicolour mode separates the two sides of the book.