Summer arrived early as record-breaking heat moved across the Far West last week. Cliff measured our first 90-degree day on Thursday, June 13. That was only 1 degree short of the record of 91 degrees set back in 1918.
The rare early June heatwave was felt in normally cool cities like San Francisco. High temperatures soared to a record 100 degrees last Monday, which was slightly higher than readings in Las Vegas on that date. That was the first time that San Francisco reported a high temperature of 100 degrees in June.
In Salinas, Calif., another city close to the California coast, high temperatures hit 105 degrees, breaking the old record of 88 degrees. In the Central Valley of California, highs were also near or above 105 degrees.
To the south, the desert areas of the Golden State were over 110 degrees last week. Thermal, Calif., hit 116 degrees. It was also hot in Portland and Seattle last Tuesday. Portland had a record-breaking 97 degrees and Seattle also broke a record with a high of 95 degrees last Wednesday.
For the rest of June, we should see some scattered shower activity this week, but most of the moisture will be to the north and over the mountains. There’s also the possibility of an isolated thunderstorm through the end of the month. However, unless we see a big downpour, June’s precipitation total is likely to end up below the normal of 1.93 inches. As of the weekend, our June precipitation total in Coeur d’Alene is just over .80 inches.
Temperatures will also be cooling down as the strong high pressure ridge weakens. After starting off in the 80s, readings should drop into the 70s around the middle of the week. Lows will also be dipping back into the 40s, so keep those sweaters handy.
Cliff and I think that the rare June big heatwave in the Far West will eventually migrate into the central portions of the country where farmers and other residents of the Great Plains and Midwest are still dealing with massive flooding. In this pattern of wide weather “extremes,” it’s quite possible that the mud from the floods will soon turn to bricks in that part of the country as conditions are expected to dry out and warm up in July.
Assuming the high pressure ridge settles over the central portions of the country, mainly across the central and southern areas, our summer season may not be as dry and hot as the ones over the previous two years. However, with the possibility of some isolated thunderstorms, there’s always the chance of dry lightning. Hopefully, we won’t see that kind of pattern later this summer.
Speaking of summer, this Friday, June 21, will be the first official day of summer in the Northern Hemisphere. This is also the time when we experience the longest day of sunlight and the shortest night of the year. In the Southern Hemisphere, by contrast, that day will be the official start of their winter season and the number of sunlight hours will be the shortest of the year.
Since we’ve already seen our first 90-degree day of the season, many are wondering if the Inland Northwest will have another hot summer season filled with many 90-degree-plus afternoons. The normal number of 90-degree days for Coeur d’Alene is 11. We should see at least 12-15 days with temperatures at or above 90 degrees this summer. There may be one day with highs around 100 degrees.
Despite the hot temperatures, the earliest 90-degree temperature in Coeur d’Alene occurred on April 24, 1977, with a high of 92 degrees. The following day, it was 94 degrees. The average high temperature in Coeur d’Alene does not hit 80 degrees until July 5.
Last year, our first 90-degree day arrived on July 5 with a high of 92 degrees. There were 16 days last July with highs at or above 90 degrees. In August, there were 9 days above the 90-degree mark, including two days with highs at or above 100 degrees. On Aug. 10, Cliff measured a record high of 104 degrees at his station in Coeur d’Alene.
In 2017, we had 32 days with highs at or above 90 degrees. The first one we had in 2017 occurred on May 30 with a high of 90 degrees. There were only two days in June of that year with readings in the 90s. July and August were hot and dry months. July had 13 days while August reported 15 days with highs at or above the 90-degree mark. Sept. 3, 2017, was the final day with a high temperature in the 90s in Coeur d’Alene.
According to Cliff’s records, the past two summer seasons in North Idaho combined were the second driest and hottest such periods on record locally in Coeur d’Alene since the inception of local record-keeping in 1895. Only the fire-ravaged summers of 1967 and 1968 were hotter and drier. But, the summers of 2006 and 2007 were the hottest and driest across parts of eastern Washington and western Montana.
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Contact Randy Mann at firstname.lastname@example.org