We’re finally seeing a change in the weather pattern toward the wetter side here in North Idaho. Late last week, Cliff measured 1.03 inches of rain from a big storm that moved through the region. That total was the first time this year Coeur d’Alene measured over an inch of rain in 24 hours.
As of late October, we are barely in a La Nada, the state between the cooler-than-normal sea-surface temperature event, La Nina, and the warmer El Nino. But, ocean temperatures continue to rise along the Equatorial regions and a new El Nino is expected to be declared very soon.
During El Nino years, our part of the country often experiences below normal snowfalls and milder conditions during the winter seasons. For the upcoming 2018-19 season, Cliff and I are expected approximately 50 inches of snow, compared to the normal of 69.8 inches. Last year, Cliff measured 90 inches at his station.
In addition to sea-surface temperatures near the Equatorial regions, another way that scientists look for El Nino and La Nina patterns are by checking air pressure differences between Darwin, Australia, and the island of Tahiti. When the difference between the two stations becomes negative, which has consistently been the case this month, conditions often point to the eventual formation of the warm water phenomenon.
A larger percentage of ocean water across the Earth is above normal 20th century levels. More than 90 percent of the warming has occurred in the oceans. Many scientists believe it is because of the increase in carbon dioxide and other greenhouse gases, while others believe it’s an increase in underwater volcanic activity.
According to the Australian Bureau of Meteorology, there is an approximate 70 percent chance, double the normal average, of a new El Nino developing late in the fall or during the winter of 2018-19. Most of the computer models that are used to predict sea-surface temperature trends are still pointing to the formation of a new El Nino, which seems to be likely based on the current trends.
For the upcoming winter, a new El Nino would mean an increase in moisture across the drought areas of the southern U.S. We’re already seeing very heavy rainfall in Texas that has led to widespread flooding, especially toward the southeastern portion of the state.
Drier conditions would be likely over the northern portions, especially later in the fall and winter season. If there is a new El Nino, snowfall totals across much of southern Canada and the northern U.S. will likely be below average levels for the winter of 2018-19.
However, we’ve had big snow days in North Idaho, even during El Nino years. Though our winter predictions call for below-normal snowfall totals, there is still a good chance for a white Christmas.
During an El Nino, the chances are much higher for an “open” or snowless winter in Coeur d’Alene and surrounding areas. Below is the top 10 list for the least snowless years that were prepared by Cliff.
THE TOP 10 MOST OPEN ‘SNOWLESS’ WINTERS (ALL BELOW 20 INCHES!)
1. 1933-34 — 11.2”
2. 1943-44 — 13.6”
3. 1987-88 — 14.1”
4. 1914-15 — 14.3”
5. 1941-42 — 14.4”
6. 1966-67 — 15.8”
7. 1908-09 — 16.1”
8. 1929-30 — 17.8”
9. 1899-00 — 19.4”
10. 1976-77 — 19.7”
By the way, on the flip side, the fifth snowiest year had 117.8 inches in 1968-69. Back in 2010-11, Cliff measured 121 inches for the fourth snowiest in recorded history. In 1915-16, the third snowiest, 124.2 inches fell. In 2008-09, the second all-time, a whopping 145.6 inches of snow fell for the season. Of course, many of us will never forget the snowiest winter season back in 2007-08 with 172.9 inches.
In terms of our local weather, there should be more showers later this week as a series of storms move in from the Pacific Ocean. Snow showers are also expected in the higher mountains and we could see some few flakes in the lower elevations in the next several weeks.
With the increased rainfall, there’s a good chance that October’s precipitation total will be above normal after months on end of dry weather. The normal rainfall for this month is 2.22 inches. It does appear that we’re moving toward a wetter weather pattern in November and December. However, most of the moisture is expected to stay over our region and away from California for at least the next several weeks.
Contact Randy Mann at firstname.lastname@example.org.