Weathercatch: Unseasonably mild greetings on winter solstice, the shortest day of the year

Congratulations, Inland Northwest. You made it to the winter solstice. After Thursday, our days will gradually grow longer and brighter.

Thursday also marks the first day of astronomical winter, which seems odd, considering how warm and snowless the weather has been during the past two weeks. If it weren’t for the holiday decorations and glowing lights, it would be hard to believe that Christmas is four days away. High temperatures reached into the low 40s this week, storm systems dropped rain and landscapes are brown.

Conditions are vastly different than one year ago, when a sharp plunge in the jet stream ushered in an arctic air mass that encased our region for five days. On Dec. 21, the high temperature in Spokane reached just 9 degrees and the overnight low fell to minus 7. Overall, it was 27 degrees below normal for that date. Also, the snow depth at Spokane International Airport was 15 inches, while today it’s zero.

The warm pattern looks like it will stick around for a while. The National Weather Service’s Climate Prediction Center is favoring above-average temperatures in the Inland Northwest to last until Dec. 28.

And we have lots of company. Mild weather is so widespread that some unlikely parts of the country may see rain on Christmas and notch their warmest Decembers on record, including Minneapolis and Fargo, North Dakota.

A trio of factors is largely responsible: A ridge of high pressure over much of the Lower 48, an influx of warm air from the subtropical Pacific and a southwesterly air flow.

Today’s solstice will bring us 8 hours and 25 minutes of daylight. Starting Friday, we’ll gain only a few seconds of daylight each day. Then it will grow to a minute, then five, and so on. By the time we reach the summer solstice on June 20, the sun will be in the sky for a whopping 16 hours – an increase of about 7½ hours.

As of now, it may take a Christmas miracle for snow to be on the ground on Christmas Day. Without cold air, any precipitation is likely to fall as rain or a mix of rain and snow. There’s a good chance we’ll see those conditions in the Spokane area on Friday and into Saturday.

Regardless of what the weather brings us, as the winter solstice draws to an end Thursday night, remember that the darkest period of the year is behind us.

Nic Loyd is a meteorologist in Washington state. Linda Weiford is a writer in Moscow, Idaho, who’s also a weather geek. Contact: ldweiford@gmail.com.