‘Here We Go Again’: NWS Predicts Another Atmospheric River Will Pass Through Western Washington Next Week

Preparing: Lewis County Emergency Management Is Closely Monitoring River Levels For Potential Flood Risk 

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Just a week after Lewis County’s latest flooding, Lewis County Emergency Management is back on guard for another round.

The National Weather Service (NWS) issued an early advisory for Western Washington on Tuesday, announcing that an atmospheric river may pass through the region next week, dropping a significant amount of rainfall into rivers already close to overflowing.

“Well Lewis County ... Here we go AGAIN!” Lewis County Emergency Management wrote in a Facebook post Tuesday night. 

Lewis County residents should expect unseasonably cold conditions starting on Thursday, lowland rain and mountain snow through the weekend and heavy rain starting Monday as the atmospheric river event enters Western Washington, according to NWS. 

“THIS we are watching VERY closely since our rivers are already full to the brim. Now we are hoping whatever prediction they are making is not correct, but either way, we will keep you posted,” wrote Emergency Management. 

NWS’s worst-case-scenario predictions for flooding caused by heavy rain last week ultimately didn’t come to pass, though the Cowlitz, Chehalis, Newaukum and Skookumchuck did see minor to moderate flooding. 



While the forecasted conditions are similar to those that led to significant flooding throughout the Chehalis Basin in January, there should be significantly less water dumped on the region this time around, according to NWS meteorologist Dr. Mary Butwin. 

Olympia’s weather station reported a record-breaking 3.99 inches of rain when an atmospheric river hit that area on Jan. 6, according to Butwin. 

“It's going to be significantly less than that, at least as the forecast stands right now. We're probably looking at closer to 1 to 2 inches over Monday and Tuesday,” she said. 

Lowland snowfall levels in the region are also expected to be significantly lower this week than they were in the days leading up to the January flooding. 

“We may or may not see snow in the lowlands but if we do, the accumulation is expected to be under 1 inch,” wrote Lewis County Emergency Management. 

River levels are hard to forecast this far in advance, Butwin said, “so it's one of those we're monitoring and seeing how it trends.”