AER ST3 lines: 12 months of actuals, a 2-month nowcast, and 12 months of model forecast. History, the nowcast, and Oct 2026 are context; the tradable barrel is Nov 2026 onward (green). Tap + to drill from an aggregate line into projects and plants; tap any row name for its source, vintage, method, and the reasoning behind the numbers. All flows in kb/d.
All figures kb/d, computed from the table below. A bullet is omitted when its value is null; nothing here is estimated beyond the model.
Paragraph summary of projected maintenance, generated from the forward maintenance calendar (annotations/maintenance_forward.yaml) and the offline-barrel registry (annotations/offline_barrels.yaml). Outages are modeled down at the project and plant leaves; the Maintenance offline row is a memo of those deductions.
September 2026 is the nowcast bridge and carries two turnarounds, both modeled down at the leaves. The Horizon 35-day turnaround began September 8 (CNRL 2026 budget guidance, 2025-12-16); September takes a -230.0 kb/d bridge at the Horizon plant leaf per the editorial ruling of 2026-09-22, which allocated 6,900 kb of the guidance-implied 10,585 kb to September. The Syncrude Coker 8-2 turnaround has been down since its planned August 20 start (Suncor Q2 2026 MD&A, 2026-08-04; deferred from Q2 per the Imperial Q2 2026 call); September is a full outage month at -77.0 kb/d on the Syncrude Mildred Lake upgrader leaf, and August carried the Aug 20-31 ramp at -29.8 kb/d. The mine dials back with the upgrader at -13.4 kb/d in August and -34.7 kb/d in September at the Syncrude Mildred Lake mined leaf (45% of the SCO rate, approved 2026-09-23), and the coker feed shortfall that is not dialed back is assumed redirected to the Suncor Base upgrader via the interconnect: a positive SCO offset of +7.2 kb/d in August (capped at the 380 kb/d demonstrated Base headroom) and +49.3 kb/d in September on the Suncor OSG upgrader leaf. Imperial's Cold Lake 3Q/4Q turnaround contributes -3.0 kb/d in each month (Imperial 2026 corporate guidance, annualized rate). All August and September figures are nowcast estimates built 2026-09-23, not AER published data.
October carries the two turnaround tails, both modeled down at the leaves: Horizon -119.0 kb/d at the Horizon plant leaf for the October 1-12 residual of the September 8 turnaround (editorial ruling 2026-09-22; the September bridge is not double-counted), and Syncrude Coker 8-2 -22.4 kb/d at the Syncrude Mildred Lake upgrader leaf for the October 1-9 tail (derived 77 x 9/31; Suncor Q2 2026 MD&A), with a mine dial-back of -10.1 kb/d and a Base upgrader redirect offset of +14.3 kb/d on the Suncor OSG upgrader leaf. October also carries a Christina Lake F/G tail of -20.0 kb/d at the Christina Lake leaf, which is an assumed repo-carry flagged as such: Cenovus Q2 2026 results (2026-07-29) state no Oil Sands maintenance planned in Q4 2026, and the next F/G turnaround is guided for 2031. Cold Lake runs -3.0 kb/d through the quarter (Imperial 2026 guidance). November carries the Suncor Base Plant Q4 maintenance at -15.0 kb/d bitumen on the Suncor OSG mine leaf and -5.0 kb/d SCO on the Suncor OSG upgrader leaf (Suncor 2026 planned maintenance table, Q1 2026 investor presentation, 2026-04-01); timing within Q4 is unpublished and the cuts are placed mid-quarter. December is Cold Lake -3.0 kb/d only. No other confirmed events fall in Q4 2026.
No confirmed maintenance sits in the model math for Q1 2027. The forward calendar is quiet: the next Horizon turnaround is targeted for 2028 (2026 Budget press release, 2025-12-16), Kearl's next planned turnaround is 2029 per the Imperial Q2 2026 earnings call (2026-07-31), and the next Christina Lake F/G turnaround is guided for 2031 on the Cenovus Q2 2026 call (2026-07-29).
No confirmed maintenance in the math for Q2 2027; the watch list is pattern-indicated only. Primrose and Wolf Lake flag in April (ST53 seasonal dip analysis (repo-computed, AER ST53)), while Firebag, Christina Lake North, and Leismer flag in May (ST53 seasonal dip analysis (repo-computed, AER ST53); ST53 seasonal dip analysis (repo-computed, AER ST53); ST53 seasonal dip analysis (repo-computed, AER ST53)). These are indicators of likely maintenance timing, not scheduled events, and carry no volume in the forecast.
No confirmed maintenance in the math for Q3 2027. MacKay River is pattern-indicated for September (ST53 seasonal dip analysis (repo-computed, AER ST53)), the strongest seasonal signal in the roster; indicator only, no volume in the forecast.
The forward calendar window ends September 2027, so Q4 2027 has no confirmed events in the model. Watch for 2028 announcements, including the targeted 2028 Horizon turnaround (CNRL 2026 budget).
Named assumptions behind the grade rows and the Coker 8-2 disposition. Guidance-sourced and pattern-indicated maintenance are kept separate throughout.
Actuals run Aug 2025 through Jul 2026 (AER ST3). Aug-Sep 2026 (amber) are nowcast estimates: each line's seasonal baseline plus confirmed maintenance events, built 2026-09-23; they are not AER published data. Oct 2026 (blue) is the last context month, post-nominations. The tradable window (green) runs Nov 2026 onward: that is the barrel that prices. Bright orange cells mark modeled maintenance offline: the Maintenance offline memo row, its per-event child rows, and every project or plant cell modeled down for an outage. A dark badge on a deducted leaf cell shows the kb/d hit; a positive badge (for example on the Suncor Base upgrader leaf in Aug-Oct 2026) shows a modeled redirect offset; tap either for the source and reasoning. The grade rows at the bottom of the table cut the same supply by grade instead of by source: SCO (which equals upgraded production), marketable bitumen (dilbit), bitumen sent for further processing (a memo, shown positive), and the grade total, which ties exactly to Total WCSB crude supply every month. See the grade-layer assumptions panel below for the named assumptions and the leaf-to-grade mapping. are AER ST53 commercial-scheme forecasts, grossed up by 1.27 so they reconcile to the ST3 in-situ line (mapped projects cover 79.0% of ST3 in-situ; the remainder sits on the "Unmapped in-situ" row). Mined bitumen and SCO drill into AER ST39 facility rows (actuals through 2026-05; Jun-Jul 2026 blank until AER publishes), with plant forecasts scaled to tie exactly to the ST3 lines. Every row carries a Why note explaining the reasoning behind its forecast: named maintenance events with dates and kb/d impacts, decline assumptions, project ramps, and where a single-month dip is just the seasonal factor repeating. Confirmed turnarounds are modeled down at the affected project and plant leaves (orange cells with a kb/d badge). Maintenance offline is a memo row that details those same outages (tap +): confirmed turnarounds with kb/d impacts, plus pattern-indicated 2027 windows that carry no volume. Implied storage change is a model output with no actuals counterpart. Unknown values are blank, never filled in.
| Publisher | Dataset | Vintage / coverage | Retrieved |
|---|---|---|---|
| Alberta Energy Regulator | ST3 - Alberta Energy Resource Industries Monthly Statistics | Actuals through 2026-07 (latest file vintage 2026-08-27) | 2026-09-22 |
| Alberta Energy Regulator | ST53 - In-situ project data (commercial schemes) | Actuals through 2026-07 | 2026-09-22 |
| Alberta Energy Regulator | ST39 - Oil sands plant data (mined bitumen and SCO by facility) | Actuals through 2026-05 | 2026-09-22 |
| Heavy Reading model | Aug-Sep 2026 nowcast (seasonal baseline plus confirmed maintenance) | Built 2026-09-23; not AER published data | 2026-09-23 |
| Heavy Reading model | sd_balance.json: 12-month forward balance, 21 granular leaves | Oct 2026-Sep 2027, built 2026-09-22 | 2026-09-22 |
| Heavy Reading model | Forward maintenance calendar (annotations/maintenance_forward.yaml) | Compiled 2026-09-22 | 2026-09-22 |