Another wetter than normal spring in North Idaho
The spring of 2020 was wetter than normal in Coeur d’Alene and across the rest of the Inland Empire. At Cliff’s station in northwestern Coeur d’Alene, a total of 4.43 inches of rain fell last month. That’s quite a change from last year as only .91 inches fell. In May of 2018, only 1.34 inches of rain was measured at Cliff’s station. The normal precipitation for May is 2.37 inches.
From January through May of 2020, a very healthy 15.01 inches of rain and melted snow had fallen in Coeur d’Alene. The normal for the five-month period is slightly less than 12 inches. The annual normal, from Jan. 1 to Dec. 31, is 26.77 inches, so it’s looking good that we’re going to have another healthy year moisturewise in North Idaho.
In terms of moisture over the last three months, our “meteorological spring,” North Idaho was wetter than normal, despite a relatively dry April. In March of 2020, Cliff measured 2.54 inches of rain and melted snow, above the average of 1.94 inches. Only 0.99 inches of rain fell in April, close to half of the normal of 1.94 inches. But, the skies opened up in May with 4.43 inches, taking our spring total to 7.96 inches.
The “astronomical” start of summer here in the northwestern U.S. begins on June 20 at 2:43 p.m. This is when our sun is directly overhead at the Tropic of Cancer, which is at 23.5 degrees North latitude. It’s also the time when the Northern Hemisphere experiences its longest day of the year. By contrast, in the Southern Hemisphere, it will be the shortest day of the year as they will be going into their winter season.
As I’ve mentioned in previous articles, although we base our seasons on the calendar, most meteorologists and climatologists break down the seasons into groups of three months. For example, the meteorological summer in our part of the world includes June, July and August. The meteorological fall begins on Sept. 1 and ends Nov. 30. The meteorological winter is from December through February and the spring includes March, April and May.
According to the National Oceanic and Atmospheric Administration, meteorological seasons are primarily based upon annual temperature cycles. For example, we really start to feel the chilly weather in December and the summer conditions in June. The spring and fall are considered to be “transitional” periods. This system actually makes it easier for scientists and forecasters to calculate monthly and seasonal statistics. They were created for observing and forecasting weather patterns, which has proven useful for agriculture, commerce and other purposes.
If you have thought many of our spring seasons have been wetter than normal, you would be correct. Over the last 16 years, the combination moisture totals of March, April and May have been near to above average. Since 2005, there was only one year in Coeur d’Alene when spring moisture totals were below average.
The wettest spring in recent history was back in 2017 with totals more than double the normal. In Coeur d’Alene, a whopping 13.83 inches of moisture fell during that three-month period. The lowest spring total was in 2015 when 6.02 inches of rain and melted snow were recorded, compared to the normal of 6.08 inches, which was 99 percent of normal, the only year during the meteorological spring when precipitation was below average.
Despite the recent trend of near- to above-normal annual moisture seasons in North Idaho, there’s usually a period of much drier-than-normal weather, especially during the summer season. Since 2015, our meteorological summer seasons of June, July and August were well below normal. In 2017, we only had 32 percent of our normal rainfall and about 57 percent of normal precipitation in 2018. Those were the years of the disastrous fires in the Far West. In 2019, Coeur d’Alene finished the summer with slightly over 57 percent of normal rainfall.
As far as 2020, the first four days of June were dry, but more rain moved into the region this past weekend. The wetter-than-normal weather pattern is expected to continue for at least another week to 10 days. Then, later this month and into July, conditions in the western portions of the country are expected to turn drier than average once again.
It will be one of those summer patterns where it won’t be “rainless,” but it will just “rain less” than normal.
In terms of temperature, there were only 8 days in the 90s in 2019. For 2020, Cliff and I believe that we’ll have around 25 days with highs at or above 90 degrees. It’s also possible that we’ll see one or two 100-degree days.
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Contact Randy Mann at randy@longrangeweather.com