A blast of cold air this week will bring Clark County its first taste of winter, forecasters said, and possibly some wintry precipitation.
Temperatures are expected to dip below freezing Tuesday night for the first time in months as strong winds funnel frigid air into the region from the east. By the time moisture arrives on Wednesday, the transition could create the right conditions for freezing rain, according to the National Weather Service in Portland.
“Our biggest concern is in the Columbia River Gorge,” said Gerald Macke, a meteorological technician with the weather service. “That’s the most likely spot to get any type of freezing precipitation.”
Freezing rain, like other winter precipitation, needs a particular recipe to materialize. When moist air gradually warms the area from above, lingering cold air in lower elevations can be enough to turn regular rain into freezing rain — if it stays in place long enough, and stays cold enough. If not, the region gets wet, but no ice.
The main threat of freezing rain arrives Wednesday night into Thursday morning, Macke said. Clark County likely won’t see widespread ice on roads, which remain relatively moist and warm after mostly mild temperatures so far this fall, he said.
“The ground is pretty warm,” Macke said. “It’s going to take a while for things to freeze.”
If hazardous conditions do materialize, particularly in the gorge, state highway maintenance crews will be ready, said Washington State Department of Transportation spokesman Bart Treece. Crews have held snow and ice meetings in recent weeks to prepare for the season, and workers watch forecasts closely this time of year, he said.
“They stay pretty plugged in so they can adjust their maintenance practices accordingly,” Treece said.
WSDOT also asks drivers to be prepared for the conditions when they hit the road during the winter months. That means keeping your car maintained, and traveling with supplies and a full tank of gas, Treece said. The agency also recommends carrying an emergency kit with items such as blankets, batteries, food, water, gloves, boots and a first-aid kit.
“Having a car break down in bad winter weather, that could be putting you in a bad spot,” Treece said.
Even if freezing rain doesn’t develop this week, the weather shift will bring undeniably cold temperatures. Overnight lows in Clark County are expected to land in the low 30s or high 20s Tuesday and Wednesday nights, according to the weather service. And gusty winds will make it feel much colder.
For example, if the temperature is 30 degrees and the wind is blowing at 30 mph — a very real possibility in Vancouver and elsewhere — the wind chill is 15 degrees, Macke said.
Depending on location, winds will vary from 25 to 45 mph with gusts up to 60 mph, according to the weather service. Forecasters on Monday issued a high wind warning for much of the region including Clark County.
Southwest Washington should see mostly rainy conditions by the end of this week with high temperatures in the 40s, according to the weather service.
