Tri-Cities wind chill dropping to dangerous lows. Bad weather keeps closing I-90, I-84

The National Weather Service is warning that the wind chill value in the Tri-Cities could drop to a dangerously low minus 20 this week amid record-breaking cold temperatures.

If your plan was to escape to Western Washington, the Washington state Department of Transportation was telling drivers not to travel on Tuesday unless you were prepared for heavy snow.

Up to 18 inches of fresh snow was forecast Tuesday for Interstate 90 at the pass over the Cascade Mountains.

In the Tri-Cities, a wind child advisory was issued for 10 p.m. Wednesday until 10 a.m. Friday.

Wind chill is the temperature your body feels when the air temperature is combined with the wind speed.

The wind chill forecast for the Tri-Cities area could cause frostbite on exposed skin in as little as 30 minutes, according to the weather service, as wind increases the rate of heat loss from skin. It also puts people at risk of hypothermia.

Check on the elderly, bring pets inside and protect pipes and plants, said the weather service.

On Wednesday night the low in the Tri-Cities is forecast at minus 5 degrees, which is colder than the record of minus 3 for the date.

But the wind chill factor is forecast to be as low as minus 20, as sustained wind speeds of 8 to 10 mph and gusts as high as 20 mph are possible.

The high Thursday could reach only 7 degrees, lower than the previous record for the coldest high temperature of 10 degrees for that date in the Tri-Cities. A north wind of around 8 mph is forecast.

Both records were set in 1990, but daily temperatures for the Tri-Cities go back more than 100 years.

Thursday night the forecast calls for a low of 4, with the high warming to 17 on Friday when the wind chill advisory expires.

If you go outdoors during the windchill advisory, wear mittens or gloves and a hat. At least half of body heat is lost if your head is not covered, says the weather service.

Dress in layers to trap warm air between loose fitting clothes as insulation and stay dry, as wet clothing allows body heat to be lost faster.

Watch for signs of hypothermia. Adults may shiver, feel very tired, be confused, have fumbling hands, lose memory, slur their speech and feel drowsy.

Babies, including those sleeping in cold bedrooms, may have bright red, cold skin and little energy, according to the Centers for Disease Control and Prevention.

Signs of frostbite include redness or pain, or a white skin area; numbness; and skin that feels unusually firm. The nose, ears, toes, cheeks, chin and fingers are most likely to be affected by frostbite.

More snow is forecast for the Tri-Cities, with a 40% chance of snow Tuesday night, Thursday night and Friday.

Saturday snow is possible in the morning, switching to rain and snow in the afternoon.

Christmas day the weather should improve, with only a slight chance of precipitation and temperatures warming to 31 degrees.

Travel forecast

If you travel this week, plan to pack your car with extra blankets and coats, says the weather service.

Tuesday both Interstate 84 in the Columbia Gorge and Interstate 90 from North Bend to Ellensburg closed to traffic.

The Washington state Department of Transportation urged people to stay home rather than cross Snoqualmie Pass on Tuesday. “Be prepared or delay trip,” it said.

I-90 closed in both directions due to slick roads and spinouts at about 11 a.m. Tuesday.

A winter storm warning for I-90 at the pass was issued after 13 to 19 inches of snow were forecast for Tuesday with another 6 to 10 inches possible Tuesday night.

Thursday night also was forecast to be snowy, followed by a wintery mix of snow mixed with freezing rain at times Friday through Saturday night. Rain is forecast on Christmas Day.

Both eastbound and westbound traffic lanes between Troutdale and Hood River, Ore., closed at 7 a.m. Tuesday because of icy and windy conditions. Several trucks had crashed, according to the Oregon Department of Transportation.

Westbound lanes reopened two hours later, but eastbound lanes remained closed shortly before noon.

A winter storm warning was issued for Interstate 84 through the Blue Mountains of Eastern Oregon at Meacham, 30 miles east of Pendleton Tuesday until Wednesday morning. Three to six inches of snow was possible.

Snow also is likely Thursday night and Friday.