State of emergency flooding – a perfect storm

By Nic Loyd, WSU meteorologist, and Linda Weiford, WSU News

SPOKANE, Wash. – As a warm sun hung over the Inland Northwest one day last week, it felt as though a giant lid had been yanked off the region. After a seemingly constant onslaught of rainy or drizzly days, the sky was blue, the temperature climbed to 60 degrees and we truly had a reason to enjoy being outside.

Not only did that balmy Thursday offer relief to sun-deprived humans, but also to our bloated rivers, streams and ponds. In parts of eastern Washington and the Idaho Panhandle, waterways were spilling onto road, fields, parks and driveways. A full day with no precipitation helped keep water levels from surging even more.

Unfortunately, the relief was short-lived.

At the start of the weekend, another storm system moved in, dropping more rain and bringing water levels back up. By Sunday morning, the Spokane River in Spokane topped its flood stage of 27 feet. Along segments of the Palouse River, ducks could be seen skimming ponding water of overflow. In the town of Sprague, Wash., creek floodwaters seeped into homes and over roads.

On Monday, Gov. Jay Inslee declared a state of emergency for flooding in 20 counties, including Whitman and Spokane.

After two back-to-back years of dry weather, flooding may seem abnormal in our region. But in fact, Washington is one of the most flood-prone states in the U.S., according to the state department of ecology, with costs of flood damage beating the cost of any other natural hazard.

Washington got pelted with an unusual amount of rain and snow this winter. Widespread melting of deep snow combined with rain dumps is what pushed waterways to their brinks and beyond.

And yet, a blend of heavy rain and snowmelt is the number one cause of floods in the Inland Northwest, which typically occurs in late winter and early spring. In western Washington, rainfall alone is the main source of flooding, occurring in late fall and early winter.

Simply put, our region is following a natural climatic rhythm. It’s just that the tempo is more intense this time around.

What to expect now that spring has officially arrived? Typical of springtime, warmer temperatures and more showers will follow. As more rain beats down on soils too saturated to drain the water away, we should expect to see more flooding and an increased risk of landslides.

 

Weathercatch is a bimonthly column that appears in The Spokesman Review. Nic Loyd is a meteorologist with Washington State University’s AgWeatherNet. Linda Weiford is a WSU news writer and weather geek. Contact: linda.weiford@wsu.edu.