Northwest to Get Wet Winter, Mid-Columbia Hydrologist Predicts

By Chris Mulick, Tri-City Herald, Kennewick, Wash.

Dec. 15–Intensifying La Nia conditions are strengthening at least one projection for a wet winter.

That forecast is delighting hydropower managers, fish advocates, irrigators and others hoping for snow.

Kyle Dittmer, a hydrologist for the Columbia River Inter-tribal Fish Commission and president of the Oregon chapter of the American Meteorology Society, recently increased his Columbia River runoff projection to 111 percent of normal. That’s for January through July runoff measured at The Dalles.

La Nia impacts haven’t yet been taken into account in the most preliminary projections being produced at the National Weather Service’s Northwest River Forecast Center. Mostly an indicator of how the water year has started out, they predict a near normal runoff at The Dalles and also in the Yakima and Snake rivers.

But those forecasts will be influenced by the consideration of additional meteorological factors starting in the next week or so.

“There is a very large band of uncertainty because we’re doing it so early,” said Harold Opitz, hydrologist in charge at the center.

Still, Dittmer believes the Northwest may be in for its wettest winter since 1999.

“Then we’d have water for everyone instead of fighting over it,” he said.

What once was believed to be a weak La Nia appears to be strengthening, Dittmer said. The oceanic phenomenon typically brings cooler temperatures and more precipitation.

The recent Pineapple Express that brought unseasonably warm temperatures still dropped lots of snow in the mountains, he said. And it now appears that cooler temperatures are in store beginning this month.

“Hopefully, most of that snow will get locked in,” Dittmer said.

La Nia conditions are expected to linger into spring, which could help preserve that snowpack until the summer months, when it is most valued.

“I think we’re looking for a good winter,” Dittmer said.

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