When Is EIA Natural Gas Storage Data Released?

The release is the Weekly Natural Gas Storage Report, EIA's estimate of natural gas held in underground storage across the lower 48 states. Underground storage operators file Form EIA-912, and EIA aggregates those responses into working-gas figures for five regions - East, Midwest, Mountain, Pacific, and South Central (split into Salt and Nonsalt) - plus a Total Lower 48 row. Each region carries six numbers: current-week stocks, prior-week stocks, net change in Bcf, implied flow in Bcf, year-ago stocks with percent change, and the 2021-25 five-year average with percent change.

The verified edition covered the week ending August 14, 2026 (released August 20, 2026): total lower 48 working gas of 3,169 Bcf, up 16 Bcf week-over-week, 28 Bcf below last year and 185 Bcf above the five-year average of 2,984 Bcf. The East region read 708 Bcf against 693 Bcf the prior week and 688 Bcf a year earlier - six figures per region, repeated across seven rows, is the whole shape of a print.

That is also the entire public geography: no state or facility detail ships with the Thursday release, so plan dashboards around the regional series plus the total rather than expecting county-level splits. The underlying wngsr.json payload does add machine context a screenshot misses - release_name, release_date, current_week, week_ago, year_ago and 5yr_avg fields plus roughly 8 series with ids like png.nw2_epg0_swo_r48_bcf.w, each carrying units in billion cubic feet.

Everything lands on ir.eia.gov/ngs/ as plain files, no authentication required:

• wngsr.csv - the current-week regional table, one row per region
• wngsr.json - the structured payload, including revision_flag and reclassification_flag booleans per metric (strip its leading UTF-8 BOM before parsing)
• wngsr.txt - the summary text release
• ngshistory.xls - the full weekly history workbook, 739 KB, roughly 1,600+ observations per region back to the mid-1990s
• ngsstats.xls - five-year averages plus max, min and year-ago statistics by week of the storage year
• cvhistory.xls - the coefficient-of-variation sampling variability archive, beginning April 2015

Two operational notes from verification. Files appear after 10:30 a.m. eastern, so poll later in the hour rather than on the stroke of release. And some ir.eia.gov paths returned HTTP 403 to plain curl while sibling paths succeeded - send a normal browser User-Agent before you schedule an automated pull.

Weekly prints move fast but stay shallow, so two monthly EIA products carry the storage picture with more depth and history. The dnav area tables, EIA Natural Gas Supply, Disposition and Prices by Area, cover roughly 45 measures x 52 areas x 2 frequencies, including underground storage capacity and working gas by state, with capacity series from 1989 and core series back to 1973, current through May 2026. The EIA Natural Gas Monthly Report ships 25 tables and 6 figures per issue in XLS and PDF, with state-level underground storage breakouts alongside production, deliveries and prices.

Timing differs by product, not just depth. The dnav area tables refresh on EIA's monthly publication cycle and were current through May 2026 at verification, while the Natural Gas Monthly carries roughly five years of monthly and annual data per issue (2021-2026 in the verified edition) inside its 12-issues-per-year archive. Both arrive weeks behind the Thursday signal - which is precisely their role: confirmation, not speed.

For most timing questions the weekly report answers first and the monthlies reconcile later. If your model needs a longer memory than the mid-1990s workbook offers, splice the monthly series behind it rather than stretching the weekly file past its verified depth - the monthlies reach back to 1973 in core series and 1989 for storage capacity, a span no weekly file matches.

A reliable pull takes five steps:

1. Schedule the job for just after 10:30 a.m. eastern each Thursday - the release is embargoed until then, and earlier polls only return last week's files.
2. Fetch wngsr.csv or wngsr.json from ir.eia.gov/ngs/ with a normal browser User-Agent header.
3. Strip wngsr.json's leading UTF-8 BOM, then read current_week, week_ago, year_ago and 5yr_avg fields plus the calculated block (net_change, implied_flow, pct-change_yrago, pct-chg_5yr-avg).
4. Check revision_flag and reclassification_flag values before booking a number - figures derive from Form EIA-912 operator responses and get corrected in later prints.
5. Reconcile weekly totals against the monthly dnav tables once a month to catch drift between survey vintages.

The payoff is speed against depth: the Thursday print reaches dashboards hours before any monthly alternative, and the 739 KB ngshistory.xls workbook supplies the multi-decade baseline those intraday comparisons lean on.