A warm and mostly dry January has depleted most of the lower level snowpack around the Columbia River basin, with record low or near record low snowpack in the Oregon and southern Washington Cascade Mountains, a condition that could contribute to lower stream flows that will be needed for salmon and steelhead migrations this spring and summer.

However, the strength of the snowpack in the northern areas of the basin and British Columbia is contributing to predictions of average to near average water supply forecasts further downriver on the mainstem Columbia River, according to a water supply briefing by Amy Burke of NOAA’s NW River Forecast Center this week.

She said the snowpack in the Cascades is “skirting historic lows,” with most of the snowpack found in higher elevations of the mountains, but little snowpack in the lower elevations. The exceptions are in Canada and the highest areas of the Cascades.

The February water supply forecast at Grand Coulee Dam, the northern-most dam on the Columbia in the U.S., is at 100 percent of normal (61,664 thousand acre feet, April through Sept.), but that’s due to above normal snowpack in the mountains surrounding British Columbia dams.

The forecast at Mica and Duncan dams in B.C. are at 110 percent of normal and the forecast at Libby Dam in Montana, also upstream of Grand Coulee, is 109 percent of normal. Forecasts are provided by the Northwest River Forecast Center.

These dams are in areas where snow water equivalent (a metric that contains the amount of water in the snowpack) are in some places at 140 to 150 percent of normal. The average SWE in the upper Columbia River is 119 percent of normal.

However, the water supply forecast at Hungry Horse Dam in Montana, also upstream of Grand Coulee, but slightly further south than Libby Dam, is lower at 84 percent of normal, having dropped a full 11 percentage points since the first of January water supply forecast.

Snake River basin water supply forecasts have also dropped, with the Lower Granite Dam forecast at just 78 percent of normal, a drop of 16 percentage points since January. Further upriver and closer to the Rocky Mountains where most SWE is near normal or better, American Falls is registering a 91 percent of normal water supply forecast, but still, that’s a drop of 27 percentage points from January.

The water supply forecast at Dworshak Dam on the North Fork of the Clearwater River is even lower at 71 percent, a drop of 10 percentage points since January. This is an area where SWE is 50 to 75 percent of normal.

Another bright spot in the basin is in the North Cascades, where the water supply forecast in the Okanogan River at Malett is 102 percent of normal, a rise of 5 percentage points since January.  The Methow River near Pateros is 117 percent of normal, a drop of 8 percentage points since January. These are in areas with SWE of 90 to 110 percent of normal.

However, further south in Washington and Oregon, where SWE is not so robust, water supply forecasts are dismal. The Yakima River forecast at Parker is just 68 percent of normal, down 13 percentage points from January, and to the east the Walla Walla River near Touchet is 58 percent of normal, down 19 percentage points. The Yakama comes out of the Cascades in an area where SWE is 25 to 50 percent of normal, and SWE near the Walla Walla is in the high 20 percent of normal.

The water supply forecast for the Umatilla River in Oregon is at 54 percent of normal, down 20 percentage points, and the forecast for the Crooked River near Prineville is 35 percent of normal, down 15 percentage points. The Grande Ronde River at Troy, a Snake River tributary, forecast is at 64 percent of normal, down 16 percentage points, and at the Owyhee Dam, the forecast is at 53 percent of normal, down a full 20 percentage points. SWE in areas surrounding these rivers varies from the high 20 percent of normal to the high 30 percent of normal.
The culmination of all this water is The Dalles Dam with a water supply forecast of 93 percent of normal, down 6 percentage points from January.

Downstream of all mainstem Columbia dams, the Willamette River water supply forecast at Salem is 75 percent of normal, down 7 percentage points from the January forecast. SWE is in mountains feeding the river is in the low to high 20 percent of normal.

Burke is worried that the basin snowpack will not improve significantly. In the first week of February, she said, much of the moisture and snowpack that can be expected in a year has already fallen. She also warned that that depends on location where the northern locations and locations higher in altitude are driven by snow, while further south and at lower altitudes they are driven by precipitation.

At The Dalles Dam precipitation is about 50 percent of the way through the year, Burke said. “The rule of thumb is that April 1 is the peak of the snowpack, but that will be later in the north and at higher elevations,” she said.

So, what’s in store for the basin’s weather? NOAA’s Climate Prediction Center’s February weather forecast calls for “leaning below” or “likely below” normal temperatures for most of the Columbia River basin with an equal chance of above/below normal in northern Idaho and western Montana.

The Center’s prediction for the month of February for precipitation is for above normal in the northern areas and an equal chance of above/below normal in the southern areas of the basin.

Looking out over the three months of February, March and April, the Center is predicting an equal chance of above/below normal temperatures for most of the basin, with below normal temperatures in the north. The precipitation forecast is for an equal chance of above/below normal in the south and above normal in the east and north.

Drought Report

The warm and dry January is leaving the Columbia basin with the worst snowpack in decades, according to NOAA’s National Integrated Drought Information System. The NIDIS’s Feb. 5 update says that the snow cover of 139,322 square miles across the western U.S. is the lowest Feb. 1 snow cover since 2001 (this includes all areas of the West, not just the Pacific Northwest).
Three states, including Oregon, are reporting record low snowpacks with critical water supply basins like the Deschutes and Yakima rivers experiencing severe snow drought.

“A lack of snow cover could result in a longer fire season or reduce runoff efficiency as snow melts,” the report says.
“Time is running short on reaching average peak median snow water equivalent, which occurs in March and April in most basins in the West,” the report says. “Snowfall deficits will be difficult to make up, but abundant snowfall over the next couple months could reduce impacts.”

According to the Feb. 5 U.S. Drought Monitor report, much of Oregon and Washington are experiencing abnormally dry conditions, with some areas seeing moderate to severe drought. Areas of moderate drought are in northeast Oregon, north and southeast Washington and Idaho’s panhandle. Severe drought is found embedded in those moderate drought areas and centering in far northeast Oregon and Idaho’s panhandle.

Areas of moderate to severe drought conditions can also be found along the Rocky Mountains in Montana, with a couple of small areas of extreme drought on the west side of the Rockies.

The Drought Monitor report says that even in areas that have received snow recently, low snowpack combined with dry soils and low stream flows led to degradations across the Intermountain West. Western Oregon saw dry and drought conditions expand toward the coast and into far southwest Washington.

For background, see:

— CBB, January 9, 2026, Recent Rains Boost 2026 Water Supply Forecast (April-Sept) For Columbia Basin But Overall Snowpack Far Below Normal, Recent Rains Boost 2026 Water Supply Forecast (April-Sept) For Columbia Basin But Overall Snowpack Far Below Normal – Columbia Basin Bulletin

— CBB, May 14, 2025, Columbia Basin Snowmelt, Runoff In Most Areas Early, Rapid; Water Supply Forecasts May-September Dropping, Columbia Basin Snowmelt, Runoff In Most Areas Early, Rapid; Water Supply Forecasts May-September Dropping – Columbia Basin Bulletin

— CBB, April 12, 2025, Some Melting In March But Columbia Basin Water Supply Forecast Improves, 90 Percent Of Average At Dalles Dam (April-Sept), https://columbiabasinbulletin.org/some-melting-in-march-but-columbia-basin-water-supply-forecast-improves-90-percent-of-average-at-dalles-dam-april-sept/

— CBB, March 15, 2025, Columbia Basin Water Supply Forecast, April-September, Remains Below Normal, Coming Precipitation Could Help, https://columbiabasinbulletin.org/columbia-basin-water-supply-forecast-april-september-remains-below-normal-coming-precipitation-could-help/

— CBB, February 7, 2025, Though Doesn’t Feel Like It Right Now, Columbia Basin Water Supply Forecast For April-September Still Dropping, https://columbiabasinbulletin.org/though-doesnt-feel-like-it-right-now-columbia-basin-water-supply-forecast-for-april-september-still-dropping/