Halloween and more winter forecasts

Winter conditions arrived last week across the Inland Northwest as many locations received their first measurable snowfall for the season. At Cliff’s station, 0.2 inches of snow fell last Wednesday. Other locations around Coeur d’Alene picked up about 0.2 to 0.5 inches. At the Spokane International Airport, the chilly storm produced 1.1 inches of snow.

High temperatures through the first three weeks of October were relatively mild to warm. The warmest day this month was Oct. 8, with a high of 80 degrees. Readings were mostly in the 60s and 70s through Oct. 21 but dropped dramatically Oct. 25 with a high of only 35 degrees in Coeur d’Alene.

For Halloween, it appears the Inland Northwest is going to be in between storm systems. Skies are expected to be partly to mostly clear, but it’s going to be very chilly. High temperatures for Tuesday are forecast to be near 50 degrees. However, as the evening progresses, readings are expected to drop into the upper 30s to around 40 degrees, so bundle up the trick-or-treaters.

As I mentioned last year, based on records going back to 1895, moisture has fallen on Halloween a little over 40% of the time in the Coeur d’Alene region. It looks like the odds will be with us this year.

The average temperatures on Halloween range from a high of 52 degrees and a low of 34 degrees. The warmest Halloween in Coeur d’Alene occurred in 1938 with a pleasant 72 degrees. Three years earlier, in 1935, it was the coldest with a low of only 2 degrees. The wettest Oct. 31 in recorded history occurred seven years ago in 2016, as 1.20 inches of rain was measured. In terms of snowfall, Coeur d’Alene did receive 3 inches on Halloween in 1971.

Last year, we had a high of 56 degrees with a low of 44. There was also .14 inches of rain that fell on that date. Also, four days later, Nov. 4, we had our first measurable snow of the 2022-23 season in the lower elevations as 3.7 inches fell in Coeur d’Alene.

Despite the recent chilly weather with a little snow, the overall snowfall season of 2023-24 is still expected to be below normal. For the Coeur d’Alene region, Cliff and I are expecting around 45 to 55 inches, which is below the 69.8-inch normal. The forecast of lower snowfall totals is mostly based on the warming of ocean waters along the equatorial regions. As I’ve mentioned previously, we’re now in the middle of at least a moderate, warmer El Niño. Many forecasters are indicating that this intensifying El Niño could be a very strong event by early 2024.

It's possible this new pattern may produce some surprises down the meteorological roadway. For example, during El Niño events, we often see normal to below-normal named storms in the Atlantic and Caribbean waters due to increased wind shear. During a typical season, there are 14 named storms. For the 2023 season, as of this writing, there have been 20 named storms with the possibility of additional systems forming over the next several weeks.

The rapid warming of ocean waters along the equatorial regions and other regions of the Pacific Ocean has also produced additional major storms that hit Mexico in October. Most recently, Hurricane Otis hit Mexico’s coastline as a major Category 5 storm. What was very unusual about this hurricane was that it was a tropical storm during the early afternoon of Oct. 24. Within a matter of hours, Otis intensified rapidly to a Category 5 and made landfall near Acapulco shortly before midnight Pacific Time. This was the strongest hurricane in history to hit Mexico’s Pacific Coast and the fastest-strengthening storm as well.

For the upcoming winter season in the Inland Northwest, some long-range forecasts for this region are a little different. The 2024 Farmer’s Almanac is predicting above normal for the Inland Northwest, but below normal along the northwestern coastline. They mention the possibility of the polar vortex moving southward and bringing more snow to the northern regions this winter season. The Inland Northwest would likely be on the edge of the polar vortex. By contrast, NOAA’s Climate Prediction Center is predicting and warmer and drier winter season in our region. We’ll have to wait and see how these patterns develop over the next four to six weeks. But, we’ve had months with big snowfalls during El Niño years but also had open winters with less than 20 inches of snow for the season in Coeur d’Alene.

In terms of our local weather, the long-range computer models are indicating a series of storms to move into the region from the Pacific. At this time, it looks like they will produce mostly rain in the lower elevations with snow in the higher mountains. Based on this pattern, November may turn out to be a wetter-than-average month. Lastly, don’t forget to turn your clocks back one hour next Sunday.

• • •

Contact Randy Mann at randy@longrangeweather.com.