US Gas Prices & the SPR Buffer — 2026 Three-Scenario Forecast
AAA national-average pump price plus the Strategic Petroleum Reserve drawdown, side by side. Three modelled paths to December: deal-and-recovery, slow grind, or escalation plus winter heating. Today: ~$4.00/gallon est. (4th straight weekly decline; Brent $78.2 Mon Jun 22 settle, war premium nearly fully unwound); SPR 340.3 mbbl per the Jun 12 EIA print (below Jul 2023 floor, lowest since 1983). Forecast re-weighted after the US-Iran deal (signed Jun 17) — deal-and-recovery is the base case.
US gas prices and the Strategic Petroleum Reserve in 2026: observed to June 23, plus three forecasts to year-end
Two charts, same x-axis. The top chart is the AAA national-average pump price — what readers actually pay. The bottom chart is the Strategic Petroleum Reserve — the federal emergency buffer that has been muffling crude price spikes from reaching the pump in full. Solid lines are observed: AAA weekly through Jun 23 est. (pump chart) and EIA WPSR prints through Jun 12 (SPR chart). Dashed lines are three modelled scenarios for Jun–Dec, re-weighted after the US-Iran deal (signed Jun 17; physical reopening began Jun 18; Bürgenstock de-confliction channel operationalised Jun 23): with the deal signed and Brent at $78.2 (Mon Jun 22 settle, −3.0%, war premium nearly fully unwound), deal-and-recovery is the base case (~55%), slow grind the middle (~30%), and re-escalation a low-probability tail (~15%). Mine-clearing ongoing (~80 mines, ~40–50 days). Underlying data: AAA ~$4.00 est. (Jun 23), SPR 340.3 mbbl (Jun 12 print, lowest since 1983).
The two charts tell the same analytical story: as the SPR draws toward its ~250 mbbl operational floor, its capacity to absorb crude spikes weakens, and the pump-price trajectory steepens. The buffer is the reason US drivers have not seen $6+ gasoline so far. With a deal now reached, the base case is that the draw pauses and the buffer rebuilds — but if the deal collapses, a renewed drawdown toward the operational floor is the path that puts $5+ gasoline back on the table.
December 2026 endpoint range — AAA national average ($3.40 base case → $5.40 tail)
Today (Jun 23) — observed
~$4.00
AAA est. ~$4.00 (Jun 22 print); continued decline from $4.065 Jun 15 (4th consecutive weekly decline). Brent $78.2 (Mon Jun 22 settle, −3.0%; war premium nearly fully unwound), WTI ~$73.5. State extremes: California ~$5.60 est., Oklahoma-area low ~$3.20 est.
Scenario 1 — Deal-and-recovery
$3.40
BASE CASE (~55%). US-Iran interim deal signs Fri Jun 19; Hormuz physically reopens over the summer, Gulf cargoes arrive Q4. SPR draw pauses near 345 mbbl, refill begins by November. National average eases below $4.00 in Q3 and toward $3.40 by year-end — near pre-conflict.
Scenario 2 — Slow grind
$4.05
MIDDLE (~30%). Deal holds on paper but physical reopening is slow (Kpler: 3–4 months to normal transit). SPR drifts to ~300 mbbl by year-end as Washington slows the draw. Pump drifts sideways in the $4.00–$4.30 band, ending near $4.05 — no relief, no spike.
Scenario 3 — Re-escalation tail
$5.40
LOW-PROBABILITY TAIL (~15%). The interim deal collapses and the strait stays shut or re-closes. SPR falls toward ~255 mbbl, near the operational floor, and the buffer weakens. Winter heating demand compounds. Year-end ~$5.40 — back above the 2022 record, the only scenario that gets there.
Reference: 2022 historical peak
$5.00 / gal June 2022, one-week record
The 2022 peak (Russia-Ukraine + post-COVID demand) is the natural comparison for "how high can it go." Scenarios 1 and 2 both stay below it; only Scenario 3 (the low-probability re-escalation tail) gets back above it, at $5.40.
Reference: SPR operational floor
~250 mbbl salt-dome hydraulic limit
Below ~250 mbbl, the four Gulf-coast salt-dome caverns cannot sustain maximum-rate pumping (brine displacement geometry). Washington would slow draws well before the floor. Currently 340.3 mbbl (Jun 12 print, lowest since 1983) — ~90 mbbl above the floor.
The headline number. What drivers pay. Y-axis $3 to $7; the 2022 historical peak of $5.00 marked as a dashed reference; the pre-conflict baseline of $2.98 visible at the chart floor.
Chart 2 — Strategic Petroleum Reserve, million barrels
The buffer mechanic. As the SPR depletes toward its ~250 mbbl operational floor, its capacity to muffle crude spikes weakens. The lower the SPR sits, the steeper the corresponding pump-price scenario above.
FebMarAprMayJunJulAugSepOctNovDec
AAA pump price — observed
SPR inventory — observed
Scenario 1: Deal-and-recovery
Scenario 2: Slow grind
Scenario 3: Escalation + winter heating
Forecast model · GEF supply-chain analysis · pump prices from AAA daily averages · SPR levels from EIA Weekly Petroleum Status Report · scenarios are illustrative, not guarantees · model refreshed June 23; deal signed Jun 17, Bürgenstock de-confliction operationalised Jun 23global-energy-flow.com · June 23, 2026
Reading the chart. The two solid blue lines are observed: the top chart shows the AAA national-average pump price climbed from $2.98 on February 26 (pre-conflict) to a peak of $4.56 on May 21, then four straight weekly declines to an estimated ~$4.00 by June 23 as crude unwound its escalation premium on US-Iran deal progress and the Bürgenstock de-confliction framework. The bottom chart shows the Strategic Petroleum Reserve falling from approximately 415 million barrels on February 28 to 340.3 million barrels on June 12 (latest EIA print) — a drawdown of about 75 million barrels since the conflict began, and now below the July 2023 low of 346.8 mbbl (the lowest SPR level since 1983). The three dashed paths bracket what happens between now and year-end, re-weighted after the interim deal. The key analytical move on this page is reading the two charts together: in the low-probability re-escalation tail, you can see the SPR slide back toward the buffer-exhaustion zone at the same moment the pump price in the chart above climbs back above the 2022 record — that is the buffer mechanic in reverse. In the base case, the SPR draw pauses and the pump eases.
Scenario 1Deal-and-recovery — Hormuz reopens, SPR refill begins. This is now the base case (~55%). The US-Iran interim deal is set to sign Friday, June 19 in Switzerland; the agreement authorizes a toll-free reopening of the strait and an end to the US naval blockade. On this path Hormuz physically reopens over the summer (Kpler estimates 3–4 months from reopening to fully normal transit), and Gulf cargoes arrive at US refineries in Q4. The SPR draw pauses around 345 mbbl as the urgent supply pressure eases; a slow refill begins by November. National-average pump price continues its current decline — easing below $4.00 in Q3 and ending December near $3.40, close to the pre-conflict baseline. The key caveat: the strait is still physically shut as of today, with insurers absent and roughly 500 ships trapped, so this path depends on the agreement translating into actual tanker movement — not just a signed document.
Scenario 2Slow grind — deal holds on paper, physical reopening is slow. The middle case (~30%). The interim deal signs but the strait reopens only gradually: insurers stay cautious, the trapped-tanker backlog clears slowly, and effective transit stays well below pre-war levels into the autumn. The SPR keeps drawing at a reduced pace as Washington preserves flexibility, ending December around 300 mbbl. With supply easing but not normalized, the national-average pump price drifts sideways in roughly the $4.00–$4.30 band rather than spiking or collapsing, ending the year near $4.05 — no real relief, but no fresh shock either. This is the "muddle through" path where the deal is real but its physical benefits arrive too slowly to move the pump much before year-end.
Scenario 3Re-escalation — the deal collapses and the SPR slides toward its floor. The low-probability tail (~15%) now that a deal has been reached. The interim agreement breaks down before or shortly after signing; the strait stays shut or re-closes; broader Middle East shipping is disrupted again. The SPR drawdown resumes through Q3, and by late autumn the inventory approaches 250 mbbl, where salt-dome hydraulics force a sharp pace reduction and the buffer effect weakens. Winter heating-oil demand compounds the pressure. National-average pump price climbs back above the 2022 record, ending December near $5.40 — the only scenario that gets there. This is the path that would revive the policy conversations (export caps, refining mandates, demand-side measures) that the deal has, for now, taken off the table.
SPR mechanicWhy the buffer is the right thing to watch. The Strategic Petroleum Reserve is not a price-setting tool, but it is the federal government's most direct lever on retail-gasoline price action. The four salt-dome caverns in Texas and Louisiana hold up to ~714 million barrels at design capacity; the operational floor — below which oil can still be drawn but not at full rate — sits around 250 million barrels (this is the hydraulic-limit number, set by the brine displacement geometry of the caverns themselves, not by policy). Above the floor, every barrel released into the crude market reduces the marginal price that gasoline refiners pay for feedstock, and that flows through to pump prices with a one-to-two-week lag. Below the floor, that mechanic breaks: the draw rate caps out at a fraction of what's needed to muffle a spike, and crude prices flow into pump prices more directly. The recent drawdown rate has been roughly 8 million barrels per week; analysts note the reserve has now broken below its July 2023 low of 346.8 mbbl (itself the lowest since August 1983), reaching 340.3 mbbl on the June 12 print — the lowest SPR level since 1983. With the interim deal reached, the base case is that this is near the bottom: the draw pauses as Gulf supply normalizes, and a slow refill begins late in the year.
State extremesWhat gas costs across the country today. Beneath the ~$4.00 national average sits a regional spread of more than $2.40/gallon, structured by state taxes, environmental specifications (California's CARB-spec gasoline costs more to refine), refining capacity, and pipeline access.
Most expensive (per AAA)
California$5.84
Hawaii$5.33
Washington$5.30
Nevada$4.86
Oregon$4.86
Least expensive (per AAA)
Oklahoma$3.27
Kansas$3.27
Iowa$3.31
Nebraska$3.38
Arkansas$3.39
The California–Oklahoma spread of $2.57/gallon is approximately 60% of the national average. In Scenario 3 this spread widens further — high-tax, CARB-spec states absorb a larger share of the price increase because their underlying refining cost structure is already stressed. For continuously updated state-level prices, see AAA's state gas-price averages.
MethodThis is a scenario forecast, not a prediction. The observed Feb–Jun pump-price line is built from AAA daily national averages; the observed SPR line is from EIA Weekly Petroleum Status Reports. The Jun–Dec branches are illustrative model paths, not guarantees; the real outcome will depend on whether the interim US-Iran deal (due to sign June 19) translates into actual Hormuz reopening, how fast the trapped-tanker backlog clears and insurers return, the rate at which Washington draws or refills the SPR, refinery uptime, winter weather severity, and whether the deal holds. Refreshed June 23, 2026, after the US-Iran interim deal was reached — with crude back near $83 (Brent settled $83.17 on June 15, a two-month low) even as the strait remains physically shut pending the Friday signing. Sources: AAA Daily Fuel Gauge Report (national average $4.065, Jun 15), EIA Weekly Petroleum Status Report (latest print for week ending June 5: SPR 349.2 mbbl, a three-year low), EIA Strategic Petroleum Reserve historical inventory, US Department of Energy SPR Quick Facts, IEA Oil Market Report May 2026, Kpler Hormuz transit estimates June 2026, TradingEconomics crude tape June 15. Per-disruption detail and the live US shortage map at global-energy-flow.com/shortages/united-states/.