Will snow be home for Christmas?
As Cliff and I have been forecasting, it’s looking like it’s going to be a tough season for snow, especially in the lower elevations. For the 2018-19 season, we’re predicting about 50 inches of snow for Coeur d’Alene, compared to the normal of 69.8 inches. However, thanks to the warming waters of the Pacific Ocean, much of the moisture that has fallen recently has been in the form of rain.
Our weather patterns did change to the wetter side in November, which was needed as our region was enduring one of the driest summer and early fall seasons in history. But, at this time of year, many residents of North Idaho are hoping for a white Christmas.
As I’ve mentioned in previous columns, based on Cliff’s climatological records dating back to 1895, whenever Coeur d’Alene has seen a white Christmas three years in a row, there has always been a fourth one. However, there has never been a fifth White Christmas, so next year may be a brown Christmas instead. As always, time will tell.
Last week’s moisture across the Inland Northwest was mostly rain in the lower elevations. The rain and snow arrived during the normally wet and mild “new moon” lunar phase. On Dec. 22, we will be entering a “full moon” lunar cycle which is often cooler. Therefore, we do see some storms that still have the potential to produce snow in the lower elevations right around the Christmas holiday. Unlike the previous years when we had a lot of snow for Christmas, this year’s total should be considerably lower, perhaps a few inches at best.
Snowfall across the Inland Northwest is always a “temperature thing.” We need colder air in the upper-levels of the atmosphere with readings at the surface around the upper 20s to near 30 degrees to produce the most snow. Lately, it’s just been too warm.
As of mid-December, we’re still officially in a La Nada, the in-between cooler than normal sea-surface temperature event, La Nina, and the warmer El Nino. However, the latest information is pointing to a weak El Nino event.
Much of the Pacific Ocean is warmer than normal. It’s estimated that over 70 percent of this ocean is showing sea-surface temperatures above average levels. The warmest areas are near Japan, the Gulf of Alaska and along the Equatorial regions. The tremendous warming of the Pacific Ocean is something I haven’t seen in my 25-plus years of watching sea-surface temperatures.
It’s still possible that a new El Nino will be declared later this month or in January. The World Meteorological Organization predicts a 75 to 80 percent chance we will see the declaration of this warm-water phenomenon between now and February.
THE MEASURING MAN
Since Cliff has been in Coeur d’Alene, he has been dedicated to the measurement of snowfall at his station. To answer the many questions concerning the times per day that local Coeur d’Alene area snowfall is measured and exactly where these measurements take place, Cliff measures the snowfall, and liquid precipitation as well, every four hours, six times a day, 365 days a year. Now that’s what I call dedication.
He also measures the snow depths at three separate locations in his back yard, including the flat deck that’s away from both the house and trees or other obstructions. Then, he averages out the three measurements for maximum accuracy. It’s almost hard to believe, but the guy has been measuring snow now for over 65 years!
Cliff systematically measures snow before it melts. If it falls as snow, it’s measured as snow. In this “banana belt” of weather, we usually see a tremendous amount of melting, especially below 2,500 feet, even in the dead of winter. Therefore, there is a loss of accuracy if snowfall is measured only once per day.
WET WEEK AHEAD
In terms of our weather for the rest of this year and into early January, we should continue to have above normal moisture as a series of storms is expected to move into the region from the Pacific Ocean. More wet weather is expected this week, but mostly in the form of rain in the lower elevations as the air masses are expected to be mild. But, as I’ve said earlier, a few degrees can make all the difference. If some of that cold air manages to sneak in, the rain could change to snow in Coeur d’Alene and surrounding regions.
As I’ve mentioned, next week’s weather pattern does look colder, so there is a chance of measurable snowfall across much of the area. There is a chance we could see some snow at the end of this week. Cliff and I also see one of those storms that is expected to arrive around Christmas Eve or Christmas Day. There is another system that may produce more snowfall toward the end of next week as well.
Despite the recent rain in the valley locations, the mountains have been getting the snow. There is about 40 inches on the ground at Silver Mountain with close to 60 inches at the summit of Lookout Pass.
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Contact Randy Mann at randy@longrangeweather.com