The 2026 Wimbledon tennis champions were crowned over the weekend which means that summer is officially here as the next Grand Slam is the US Open. The Pacific Northwest is crossing its own summer threshold this week as every balancing authority from British Columbia to California and over to the Rockies is serving up some heat. Mid-C bilateral prices jumped roughly $20 off the weekend package to open the week, hydro has settled into a normal, gently declining pattern after a strong spring runoff, wind has gone quiet for the first half of the week, and the natural gas fleet backing up the grid pushed nominations above 1.0 Bcf for the first time since the middle of winter. Four forces, one storyline: summer has arrived in the Northwest, and gas is picking up the slack.

Heat Moves In, and Mid-C Feels It First

The clearest signal is on the price, specifically the Mid-C bilateral peak power, which had been trading in the low-$30s through the second half of last week and held flat at $31.52 for the two-day weekend package, before jumping to $51.78 for today (a $20 move in a single session). SP-15 climbed alongside it to $38.91, but the more telling detail is the spread: Mid-C is now trading at nearly a $13 premium to SP-15, well above the $4.50 gap that held through the back half of last week. For most of the year the Northwest is the discount market, leaning on hydro and importing from California when it needs to. That gradient has effectively flipped, and it is the cleanest evidence that the regional heat wave is now the dominant driver of price.

Load is telling the same story from the demand side. Peak load is forecast to jump from 21,452 MW on Sunday to 23,887 MW today, and to keep climbing to 24,584 MW Tuesday and 24,757 MW Wednesday before leveling off later in the week. That two-day ramp is exactly the window the heat is expected to move through the region, and it is what is keeping Mid-C supported even as the supply side stays comfortable.

Table 1 | Mid-C / SP-15 Peak Bilateral Pricing ($/MWh)

Hydro Holds Steady After a Strong Spring

On the supply side, hydro is doing exactly what a normal midsummer profile should do. After a spring of high output, the hydro forecast has leveled off in the 11,500 to 11,700 MW range and is easing only gradually from here, roughly 11,734 MW today drifting down to 11,494 MW by July 18. Grand Coulee has finished its refill, so the system is no longer holding back water to fill storage, and the small releases now supplementing the waning natural inflows are enough to keep the decline slow rather than sharp. Figure 1 shows the current path sitting almost exactly on the five-year average band, a marked contrast to last year’s much lower trajectory over the same stretch and a signal that hydro is a source of stability this week rather than a swing factor.

Figure 1 | Pacific Northwest Hydro, Actual/Forecast – Heavy Load

Wind Takes the Week Off

Wind is the one variable supply working against the grid this week. The forecast has average hourly output sitting below 1 GW today at roughly 822 MW, and it stays modest through midweek, 1,365 MW Tuesday and 1,681 MW Wednesday, before a brief spike to 3,730 MW on Thursday and a quick fade back to the 1,200 to 1,800 MW range into the weekend. Figure 2 shows just how far below both the five-year average and last year’s path the fleet is running through the middle of the week, a genuine lull rather than routine variability. With hydro flat and wind light, essentially all of the incremental load this week has nowhere to go but the gas fleet.

Figure 2 | BPA Wind, Actual/Forecast – Heavy Load

The Gas Fleet Answers the Call

All this comes together on the pipelines. The combined high power price and rising heat rate signal pushed regional gas nominations to 1.09 Bcf/d today (+ .135 BCF on the day) and the first time the region has crossed such a level since the middle of winter. The move is broad based rather than concentrated in one area of the grid as GTN-side deliveries rose to .492 BCF with Hermiston and Lancaster already running flat out, while NWP jumped .132 to .598 BCF as peaking units that had been sitting idle came back online, Grays Harbor from .000 to .090 BCF and Frederickson-BPA from .005 to .040 BCF among the largest swings. Today’s total is also running above the same date last year (.9997 BCF), underscoring that this is not just a seasonal formality but a genuinely tight setup.

Table 2 | Pacific Northwest Natural Gas Pipeline Nominations (MMBtu)

The Takeaway

Four threads, one rope: heat pushing load up two more days before it levels off, hydro contributing a steady but no longer growing supply, wind sitting out the first half of the week, and gas stepping in to cover the difference. With all units now in play and nominations already through the 1.0 Bcf mark, the region has clearly crossed its own threshold into summer, and the gas fleet/transmission battles, not hydro or wind, are the story to watch for the rest of the summer.

For more information about the Energy GPS Market Analytics Market Fundamentals Product Offering, please utilize the Contact Us form on the Energy GPS website or email us at [email protected].  If you are attending the Mid-C Conference this week, I look forward to seeing you.

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