Autumn means moisture headed our way

A storm system finally moved into the region on Sunday, Aug. 26 and Monday, Aug. 27, that produced 0.61 inches of rain at Cliff’s station in Coeur d’Alene. The last time we had any significant moisture in Coeur d’Alene was back on June 9 when 0.61 inches of rain fell.

For the season to date, Coeur d’Alene’s total stands at 18.07 inches. Despite the dry summer, we are still above normal for 2018 as the average to date is over 16 inches. Last year, Cliff measured about 26 inches of moisture from Jan. 1 through Sept. 3. The normal for an entire season in Coeur d’Alene is 26.77 inches.

Thanks to the recent storm, the June through August period wasn’t as dry as the one last year. For 2017, Cliff measured 1.21 inches of rain in June, 0.03 inches in July, and 0.07 inches in August for a total of 1.31 inches. The normal precipitation for June through August, the meteorological summer season, is 4.08 inches.

For 2018, June had 1.63 inches of rain, July had only 0.04 and August had 0.61 inches for a total of 2.28 inches. The three-month period was still drier than normal, but a little better than last year. However, we did see one of the worst wildfire seasons across much of the Northwest as well as California.

According to the latest information from the National Interagency Fire Center, there are about 100 wildfires burning across the U.S., mainly in the western portions. Nearly 2 million acres have been burned from these blazes alone.

Since Jan. 1, approximately 6.9 million acres went up in smoke. In 2017, the figure was close to 7.2 million acres from Jan. 1 through the end of August. The 10-year average from Jan. 1 through Aug. 31 is over 5.3 million acres.

The meteorological fall season began on Sept. 1 and will end on Nov. 30. But, the first day of astronomical fall begins on Sept. 22 at 6:54 p.m., which is based on the position of the Earth relative to the sun.

In just over two weeks, the sun will be at 90 degrees, or directly overhead, at the equator. The next time the sun’s rays will be over the equator will be the first day of spring, which is called the Vernal or Spring Equinox. That will happen on March 20, 2019.

During the first day of fall and the first day of spring, the sun will be directly overhead at the equator. Every place on the planet around that date will experience 12 hours of daylight and 12 hours of night. Elevation and location within the time zone usually create slight variances for sunrise and sunset times on first days of fall and spring.

As I mentioned in previous articles, the fall of 2018 in Coeur d’Alene and the rest of the Inland Empire looks wetter than normal. Cliff and I believe we should see another 17 to 18 inches of rain and melted snow for the rest of this year, which would be another above-normal year for precipitation in Coeur d’Alene and surrounding areas.

In terms of the fall forecast, there is a chance of some rainfall next week. Then, it will turn mostly dry with more rain expected around the “full moon” cycle of Sept. 24. The normal precipitation for this month is 1.48 inches. In 2017, September’s moisture total was 1.44 inches. Based on current patterns, this month’s average precipitation should end up close to normal.

October’s and November’s precipitation total should turn to above-normal levels as more Pacific storms are expected to move into the region. October’s normal precipitation is 2.22 inches and November’s average moisture total is 3.07 inches. Last year, October finished slightly above normal with 2.48 inches, but November had 5.27 inches of rain and melted snow.

In November 2017, 9.5 inches of snow fell, compared to the normal of 8.7 inches. For this year, snowfall totals may be below average in November if the warmer El Nino sea-surface temperature event forms in the waters of the south-central Pacific Ocean.

December may also be another month with near- to above-normal precipitation in Coeur d’Alene. In 2017, December’s moisture total was 4.24 inches, compared to a normal of 3.90 inches. Cliff measured 32.9 inches of snow for the last month of 2017, much above the normal of 20.6 inches.

For the final month of 2018, there is a decent chance we’ll see more snowfall that may give us a fourth consecutive year with a White Christmas. Since 1895, when there were three back-to-back-to-back years with a White Christmas, there was always a fourth. But, assuming El Nino forms, snowfall totals for the 2018-19 season in North Idaho are expected to be below normal. Stay tuned.

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Contact Randy Mann at randy@longrangeweather.com.