Enercast

Operational Flow Order - Imbalance

SEV 4/5Operational Alert6 days
Summary
Transco has issued a Critical OFO for imbalance management in Zone 5 due to extreme temperature forecasts, effective August 12, 2026 through August 15, 2026, with a second OFO window running August 17-18, 2026. The OFO targets deliveries in Zone 5 with a 7% Due From Shipper tolerance and a $50/dt/day penalty for violations. Zone 5 capacity data from the prior gas day (2026-08-11, one day stale) shows ZONE 5 SEGMENT HB at 1.47 Bcf/d scheduled against 1.47 Bcf/d operating capacity -- 0.0% headroom -- consistent with the OFO declaration, though this reading predates the OFO effective date by one day.
Trading note
Transco Zone 5 OFO with 0.0% headroom on ZONE 5 SEGMENT HB (1.47 Bcf/d fully subscribed as of the prior gas day) and extreme heat driving Mid-Atlantic power burn demand; expect bullish pressure on Transco Zone 5 basis versus Henry Hub, with Zone 4 basis (already at +1.150 vs HH as of 2026-08-11, versus a 5-day average of +0.840) also at risk of widening further given upstream tightness at CS 84 (3.4% headroom) and CS 60 (effectively zero headroom at 0.05% headroom).
Reroute potential
Limited: Transco is the dominant Mid-Atlantic pipeline and Zone 5 is the primary delivery corridor into that market; Tennessee Gas Pipeline (TGP) serves overlapping Northeast/Mid-Atlantic markets but typically operates near capacity during heat events, and SNG provides no meaningful relief for Zone 5 Mid-Atlantic deliveries.

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View original notice text (as posted by Transco)
Pipeline: Transco
Notice: Operational Flow Order - Imbalance
Posted: 08/12/2026 03:20:34 PM
Notice ID: 17158615

Notice 17158615

TRANSCONTINENTAL GAS PIPE LINE COMPANY, LLC

Critical:
 Y

Notice Eff Date:
 08/10/2026

Notice Eff Time:
 09:00:00 CDT

Notice End Date:
 08/15/2026

Notice End Time:
 09:00:00 CDT

Notice ID:
 17158615

Notice Stat Desc:
 Supersede

Notice Type Desc:
 OFO

Post Date:
 08/12/2026

Post Time:
 15:20:34 CDT

Prior Notice:
 17151787

Reqrd Rsp Desc:
 Immediate response required of an operational nature may be required of impacted shippers

Rsp Date:
 

Rsp Time:
 

TSP:
 007933021

TSP Name:
 TRANSCONTINENTAL GAS PIPE LINE COMPANY, LLC

Notice Text: 
Subject: 
Operational Flow Order - Imbalance

Transco provides notice of limited flexibility in managing system imbalances due to continued extreme temperature forecasts in Zone 5. In order to maintain operational pressures and adequate gas supplies required to provide an efficient and reliable firm service, Transco is issuing an Operational Flow Order (OFO) pursuant to Section 52 of its General Terms and Conditions of it’s Tariff.

 

Please refer to the table below for the effected zones, dates and tolerance percentages.

Beginning Gas Day:

Wednesday,

August 12, 2026

9:00 AM CT

Monday,

August 17, 2026

9:00AM CT

Ending Gas Day:

Saturday,

August 15, 2026

9:00 AM CT

Tuesday,

August 18, 2026

9:00 AM CT

OFO Area(s):

 
Zone 5

Zone 5

Tariff Reference for OFO Issuance:*

 (d)

(d)

Type of OFO:

 Imbalance

Imbalance

Type of Imbalance:

Due From Shipper

Due From Shipper

Transactions Include:

Deliveries**

Deliveries**

Beginning Cycle:

Timely

Timely

Tolerance % Allowed (or 1000  dth, Zone whichever  is greater):

Due From Shipper 7%

Due From Shipper 7%

Affected Shipper(s)  (DUNS #):****

 

 

Affected Location(s) (DRN  #/Loc ID):*****

All

All

Retro Scheduling Available

Yes

Yes

OBA Subject to OFO:

No

No

         If Yes, OBA Parties   (DUNS #):***

 

 

 

*Circumstances under which Seller may determine that an OFO must be issued include, but are not limited to in Section 52.2 of Transco's FERC Gas Tariff General Terms and Conditions: 

Responding to an event of force majeure; 

Accommodating capacity limitations resulting from the need to perform maintenance and/or repairs; 

Ensuring current and future storage capabilities and maintenance of line pack; 

Maintaining operational pressures and adequate gas supplies required to provide an efficient and reliable firm service;

Responding to any event which Seller believes in its sole judgment may jeopardize the integrity of its system.

** OFO based on all transactions with deliveries in affected OFO area.                                

***OFO based on all transactions with receipts in affected OFO area.                                 

**** If specific DUNS #s have been identified, only imbalances created by those shippers/OBA parties will be subject to the OFO provisions.

*****If specific DRN #/Loc ID's have been identified, only imbalances created at those location(s) will be subject to the OFO provisions.

This OFO is directed to shippers consistent with Section 52 of Transco's FERC Gas Tariff General Terms and Conditions with a minimum of $50 per dt per day penalty. This OFO will continue until further notice. Buyers with imbalances greater than the allowed tolerance will be subject to penalties specified in Section 52 of Transco's FERC Gas Tariff General Terms and Conditions.                                       

Additional information on Operational Flow Orders is available at this link:         

http://www.1line.williams.com/Transco/files/training/Critical_Day.pdf
                        

Please contact your Transportation Services Representative if you have any questions.
ID: TRANSCO-17158615  |  Rev. 1  |  Posted: 2026-08-12 20:31  |  Direction: Bullish All Transco notices  ·  page generated 2026-09-26 06:43 UTC