SPOKANE — Just days after temperatures plunged below zero, a warm weather pattern could bring flooding to low-lying areas early this week. Freezing rain drizzled across the Inland Northwest on Christmas morning and afternoon as temperatures rose, leading to slippery roads and leaving layers of ice on parked cars.
“The good news is the arctic air is going away,” said John Fox, a meteorologist for the National Weather Service in Spokane.
The high on Tuesday could reach 50 degrees in Spokane, and with it, rain on top of snow melt.
The worst of the flooding is expected in southeast Washington over the Palouse region.
In the Spokane and Coeur d’Alene area, there could be some urban flooding in low areas or where stormwater drains are plugged with snow and ice, Fox said.
Precipitation is expected to continue Monday as the temperature warms above freezing, with a high in the mid-30s. An inch of rain is forecast at lower elevations Monday through Tuesday night, while upwards of a foot of snow is expected in the mountains at elevations above 3,500 feet.
The mild weather Tuesday will lead to rapid low elevation melting snow and increased runoff, mainly across Spokane County, southeast Washington and the southern half of the Idaho Panhandle. Minor field flooding will be a concern in areas of poor drainage.
Of rivers the weather service provides forecasts for, Paradise Creek in Moscow is the only one in the region currently predicted to reach flood levels, Fox said Sunday.
Other rivers and creeks, including Latah and Rock creeks in southern Spokane County and much of the Palouse River Basin, may see rapid rises. Since many creeks and small streams are frozen, ice jams may occur.
Temperatures will cool slightly on Wednesday, but lows will remain near freezing for the rest of the week. “That will slow the snow melt a little, but it won’t stop it,” Fox said.
Some smaller storms may pass through during the rest of the week, with a chance of heavier precipitation again on Friday.
When the temperature reaches 32 degrees in Spokane, it will break a nearly two-week streak of highs below freezing since Dec. 13, Fox said.
In the Cascade Mountains, extreme ice caused Stevens Pass on Highway 2 and Snoqualmie Pass on Interstate 90 to close Saturday. Stevens Pass remained closed Sunday, while Snoqualmie Pass reopened at 10 a.m.
The eastbound Winchester rest area 25 miles east of Vantage on I-90 closed due to a broken pipe, according to the Washington State Department of Transportation.
