New lunar cycle could bring us snow
After a very early start to the snowfall season across North Idaho and the rest of the Inland Empire, November was practically snowless as Cliff measured only 0.1 inches. In downtown Coeur d’Alene and other areas, there was no snow to be seen.
Since late September, 6.7 inches of snow has been measured at Cliff’s station in northwestern Coeur d’Alene through November 30. The normal to date is about 10 inches. At the Spokane International Airport, a total of 7.5 inches of snow has been measured through November 30, topping Coeur d’Alene’s seasonal total, which does not happen very often as we normally receive much more snow than Spokane.
Last Tuesday, while much of North Idaho didn’t receive any snowfall, the Spokane area picked up over a half-inch of snow in 25 minutes that resulted in a 60-car pileup that made national headlines and shut down Interstate 90 for several hours.
Many residents and tourists were hoping for more snow for the Thanksgiving holiday, but the big western storms last week and over the weekend sent much of the moisture to the south.
Weather patterns, especially in the Northwest, will often move in cycles of about 6 weeks that are primarily based upon the lunar phases. For example, during the six-week cycle of mid-September through late October, we had the record snows and cold weather. The pattern moved to the east and we were left nearly snowless, the fourth time in recorded history with much of the region not measuring any snow for November.
We’re now entering a new six-week weather cycle and it looks like that much of the Northwest will have colder and snowier weather, especially toward the end of next week. Many of the long-range computer models are already showing this big weather change.
Assuming this pattern develops, Cliff and I believe that we should have more snow across the Inland Northwest in December. Also, sea-surface temperatures have warmed up, and we’ve often seen much higher-than-normal snowfall totals at this time of the year. However, if ocean waters continue to climb, then snowfall totals could be lower after mid January. Remember, to have the big snowy season, we need very low sunspot activity and the cooler-than-normal sea-surface temperature event, La Nina, in the waters of the south-central Pacific Ocean. Right now, we’re officially in a “La Nada,” the in-between warmer El Nino and cooler La Nina.
We’ll just have to wait and see with these crazy weather patterns. So far, it’s been a very cold and snowy start to the 2019-20 snow season across much of the northern U.S. And, rare early-season snows have been reported in the southern U.S. as well.
Many of our long-range forecasts are based upon the lunar cycles. Farmers have been planting by the moon for thousands of years. Everyone agrees that the full moon, and even the new moon, lead to noticeable changes in ocean tides. We believe that if the lunar cycles can affect the tides of the oceans, they why not the tides of the air.
Potent storm systems usually need the support of the upper-level winds as they move across the continents to produce significant precipitation. Long-time observations and data analysis do show a correlation with the lunar cycles and behavior of the upper-level jet stream patterns.
During the full moon and new moon cycles, upper-level winds will change as the low pressure troughs, or dips in the jet stream, become greater while the high pressure ridges will amplify, especially toward the end of the cycle. By contrast, during the first and last quarter lunar phases, the jet stream often becomes more zonal and storm systems are usually not as intense.
In addition to the increased moisture, our area will often see its coldest weather in the winter and its hottest temperatures in the summer during a full moon event as the troughs and ridges become more pronounced.
Cliff did an analysis of the volume of precipitation during all lunar cycles in the about 4 years ago. His data shows that North Idaho received a whopping 80 percent of its total moisture during the full and new moon lunar cycles. During the last and first quarter cycles, only 20 percent of the season’s moisture was received.
During the full moon phase, it’s estimated that approximately 40 percent of measurable precipitation falls in our region. The new moon cycle was also near 40 percent. The normally dry and warm last quarter reported less than 10 percent of moisture while the first quarter had slightly more than 10 percent of the season’s precipitation.
These cycles don’t work every single time, but we have found that they are reliable about 75 to 80 percent of time, especially in the Northwest. Those a pretty good odds.
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Contact Randy Mann at randy@longrangeweather.com