Cold/Wind Chill in West Slopes Southern Cascades and Passes, Washington

An extensive arctic airmass spread over the entire Pacific Northwest the week before Christmas. Temperatures fell sharply beginning December 18 and were coldest around the Winter Solstice December 21. High temperatures were only in the teens and 20s then. The lowest temperatures in Southwest Washington were in the Cascades, where overnight lows fell into the teens below zero. Light snow, less than one inch amounts, fell on the 19th and 21st, causing widespread traffic problems. Numerous accidents on Interstate 5 near the Oregon/Washington border during rush hour on the 21st caused a massive traffic jam. Plumbers were kept busy repairing frozen and burst water pipes.