Northwest hydro outlook trending below normal on drier February; prices climb

Despite a series of winter storms across the Western US that prompted the California governor to declare a state of emergency, the same precipitation levels haven't hit the Northwest.

The hydro outlook across the Pacific Northwest is trending below normal which could mean less available surplus energy available to send to California during peak demand season.

"It would take kind of a record year to get us to normal here," Amy Burke, a hydrologist with the Northwest River Forecast Center, said about precipitation and The Dalles Dam water supply forecast during the March 2 NWRFC water supply briefing. "We had a dry and cold February compared to normal. Our runoff year to date is well below normal."

Market impacts

Hydro generation in the Northwest has averaged 70% of the total fuel mix for February, a drop of 7 percentage points from a year ago and down 3.4 points month on month, according to Bonneville Power Administration data. So far this year, hydro has accounted for nearly 72% of the fuel mix, tumbling 7.5 points from a year ago.

"Based on current runoff forecasts, as well as colder than normal weather continuing through March, I would look for Pacific Northwest hydro output during second quarter and third quarter to be down about 15% year over year," said Morris Greenberg, senior manager of North American power analytics with S&P Global Commodity Insights.

The market has reacted to the weaker hydro supply. Mid-C on-peak day-ahead prices reached a year-to-date high of $249.13/MWh Feb. 24-25, and prices averaged 129.5% higher for the month compared with a year ago, according to pricing data from Platts, part of S&P Global Commodity Insights. Mid-C on-peak real-time prices averaged $73.52/MWh, a spike of 108% year over year.

In power forwards, Mid-C on-peak April is currently in the mid-$70s/MWh, more than double where the 2022 package ago year ago, while on-peak May is in the low $50s/MWh, 89% higher, according to Platts data. Likewise, the on-peak June package is 100% above where its 2022 counterpart was a year ago, while the July package is 77% higher and August is 39% higher.

Water supply forecast

The Dalles Dam water supply forecast is currently at 83% of normal for the April-September forecast period, unchanged from a month ago, but plunging 13 percentage points year on year, according to NWRFC data. The water supply forecast year runs Oct. 1-Sept. 30.

Inflows at The Dalles were down 26% year on year to average 121.47 thousand cubic feet per second (kcfs) in February, according to US Army Corps of Engineers data. The decrease of water into reservoir led to less power generation. Generation at The Dalles averaged 762.86 MW in February, a drop of 25% year on year, according to Corps of Engineers data.

The Dalles Dam, located on the Columbia River, serves as the barometer for hydro conditions in the region. It serves as an indication of potential surplus energy for imports into California from the Northwest. Less hydro generation in the Pacific Northwest translates to less generation available for exports to neighboring regions.

Snowpack development

"February was a cold and dry month," Burke said, adding that precipitation under 5,000 feet generally does not contribute to water supply forecasts.

Snow and precipitation in the Lower Columbia above The Dalles was at 75% of normal by the end of February, up 1 percentage point from the beginning of the month, Burke said.

Water year-to-date adjusted runoff at The Dalles fell 3 points month on month to 61% of normal. Runoff has been running a deficit every month since October, and Burke said she expected that deficit to continue, with May having the biggest deficit.

Outlook

The three-month outlook indicates greater chances for below-normal temperatures in the Northwest with equal chances for below- or above-normal precipitation, according to the Climate Prediction Center.

Most models indicate a return of El Niño-Southern Oscillation neutral conditions, which means neither El Niño nor La Niña.

For May through July, a return to El Nino conditions is expected, Burke said, which means the start of the snowmelt season.

Winter storm impacts

California Governor Gavin Newsom proclaimed on March 1 a state of emergency in 13 counties after severe storms in late February brought damaging wind and historic precipitation, including snowfall in areas not used to snow.

The storms continue to threaten power outages, according to the proclamation.

Additional storms are forecast to bring strong winds, blizzard conditions, above-normal precipitation and cold temperatures.