Coeur d'Alene's first frost

It’s almost hard to believe that about six weeks ago we were talking about very hot weather in North Idaho and surrounding regions. For the summer of 2018, there were 24 days with high temperatures at or above 90 degrees. This includes two days with readings at or above 100 degrees. The hottest summer day was on Aug. 10 with a record 104 degrees.

Today is the first day of October and now our attention will turn to colder weather and freezing temperatures. In late September, readings dropped to near 30 degrees in the outlying areas around Athol, Twin Lakes and Rathdrum. Snow has already been reported in the higher mountains in Montana.

Based on the latest information, we could see a hard freeze as early as the beginning of next week across North Idaho. The next best chance for freezing temperatures in the lower elevations would be toward the middle to the end of the month.

Although, it’s Oct. 1, there have been hard freezes in September. Based on Cliff’s records dating back to 1895, the lowest temperature in September was 17 degrees. That occurred on Sept. 24, 1926. The following morning, Sept. 25, 1926, the low was 22 degrees. That chilly period was also the only time when measurable snow was reported, as an inch fell on Sept. 23, 1926.

Since 2000, the only September freeze in Coeur d’Alene happened on Sept. 24, 2005. The morning low on that date was 32 degrees.

Since 1895, the average date for the first freeze in Coeur d’Alene is Oct. 16. The coldest reading ever recorded for October occurred on Oct. 31, 1935 with a low of 8 degrees. More recently, the chilliest temperature was 19 degrees on Oct. 9, 2009. It was 20 degrees on Oct. 10, 2009. Two days later, in the same year on Oct. 12, the mercury dipped to a frigid 15 degrees. That was the worst early October coldwave to hit the region in history.

We continue to endure this pattern of wide weather “extremes” across the globe. Early snows have already been reported in Canada. Edmonton, Alberta reported 9 inches of the white stuff last week, breaking the previous record of 5 inches set back in 1965. Early snowfalls north of the border were also seen across Manitoba and Saskatchewan. Amounts were significant enough to topple trees and take out power lines in parts of Manitoba.

Speaking of snow, there have been instances of measurable amounts of the white stuff in October in Coeur d’Alene. The most that fell was back in 1957 with 6.8 inches. Cliff’s records for Coeur d’Alene say that 3.0 inches fell on Oct. 22 and 3.8 inches was reported on the 23rd. There was one Halloween day when 3 inches of snow fell. That occurred back in 1971. The odds of measurable snowfall this Halloween in the lower elevations are very small, but in this wild pattern of extremes, anything is possible.

Cliff and I don’t expect to see much, if any, snowfall this month in Coeur d’Alene. However, don’t be too surprised to hear about some snow in the higher mountains, especially early next week. At this time of year, temperatures are usually too warm in the lower elevations across North Idaho, but anything is possible during this wild cycle of extremes.

Also, ocean temperatures are warming up in the south-central Pacific Ocean. It’s quite possible that a new warmer, El Nino, sea-surface temperature pattern will be declared later this fall and continue into the winter season. During El Nino years, our region — as well as the rest of the northwestern U.S. — often experiences below normal snowfalls. Based on these developing patterns, Cliff and I see seasonal totals falling below the 69.8-inch normal in Coeur d’Alene.

In the near-term, the strong high pressure ridge that has been dominating much of the western weather patterns with drier-than-normal precipitation will hold on into at least early October. As of late last week, there are still over 70 large wildfires burning across the West that have consumed about a million acres. Since Jan. 1, over 7.7 million acres have been burned across the U.S., most in the western portion of the country. The 10-year average is close to 6 million acres that are burned from Jan. 1 through the end of September.

We should see some much-needed rainfall this week and again around the Oct. 9 “new moon” cycle. We could certainly use the water as Cliff has told me that this period from June 2 through Oct. 2 has been the driest in recorded history. Only 1.02 inches of rain has been measured at his station since June 3. The previous record was 1.44 inches in 1929.

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Contact Randy Mann at randy@longrangeweather.com.