Update: Flooding fears ease for Tri-Cities area. Yakima River still running high
UPDATE: The outlook for flooding was reduced as of Wednesday, March 2.
The forecast then called for the Yakima River at the Kiona Gauge to crest at about 10.5 feet on Friday.
Minor flooding starts at 13 feet, and when the river rises to 11 feet, people living near the river are advised to use caution and prepare for flooding.
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Original story Feb. 28: Avalanche threat closed I-90. Flooding near Tri-Cities, WA
Rain in the East Cascade Mountains is forecast to cause flooding of the Yakima River and contribute to the threat of avalanche danger in the West Cascades, causing two mountain passes to close Monday.
A 72-mile stretch of Interstate 90, which goes over Snoqualmie Pass, closed in both directions about 2 a.m. Monday. The I-90 stretch from Ellensburg to North Bend was expected to be closed until 5 p.m.
The Washington State Department of Transportation closed the roadway due to avalanche danger, it said.
“Widespread avalanches large enough to bury and kill you are expected at Snoqualmie Pass on Monday,” the Northwest Avalanche Center posted.
“This won’t be the day to try to tiptoe around the hazard,” it said. “Stay well away from anywhere avalanches can start, run or stop until these very dangerous conditions have subsided.”
Rain saturating previously dry snow creates dangerous avalanche conditions, it said.
Warming temperatures were expected to turn precipitation to rain on Monday through Wednesday at Snoqualmie Pass. The heaviest rainfall was expected Monday with 3 to 5 inches forecast from morning through the night.
Stevens Pass, where avalanche danger was also high, closed Monday, but White Pass remained open.
Flood watch
The National Weather Service has issued a flood watch for Yakima County, and the Yakima River is forecast to flood in West Richland.
Heavy rainfall in the Cascade mountains and warmer weather melting snow will cause the river, plus smaller streams fed by the East Cascades, to rise sharply, said the weather service.
The river is expected to reach 13.4 feet on Thursday, which is considered minor flooding, at the Kiona gauge, the closest gauge upriver from the Tri-Cities.
West Richland pastures and roads near the river flood at 13 feet, according to the weather service.
The river is forecast to start rising rapidly on Tuesday, reaching 11 feet by Wednesday. People should use caution around the river then and animals should be removed from pastures by the river.
Tri-Cities forecast
A rainy week is forecast for the Tri-Cities, with warm early March temperatures.
In a typical March, highs increase from a normal of 53 at the start of the month to 63 at the end of the month. Normal lows start at 31 and increase to 39 by the end of the month, according to weather service data.
Tuesday should be the warmest day of the week with a high of 65 degrees, followed by highs in the mid 50s through the Weekend.
Monday night was forecast to be the warmest night of the week with a temperature of 51. Lows should be in the 40s through Thursday night and remain above freezing through at least Saturday night.
On Tuesday, a 20% chance of rain is forecast, increasing to 50% Wednesday and then dropping to 30% on Thursday. No rain is forecast for the weekend.
This story was originally published February 28, 2022 at 10:24 AM.