A dangerous heat wave grips the far west

Dangerously hot and record-smashing heat will be locked in over the Inland Northwest this week. In Coeur d’Alene, we’re already seeing record-breaking heat as temperatures in many locations went over the 100-degree mark Sunday. For this week, especially the next few days, the heat is going to be intense. Portland may go as high as 115 degrees this afternoon.

It’s quite possible that will we will tie or break the all-time high temperature in Coeur d’Alene of 109 degrees on Tuesday. Temperatures of 110 degrees or higher are expected across eastern Washington and down into Lewiston. Places like Omak and Moses Lake may hit 115 degrees tomorrow. And, it looks like readings will be near or over 100 degrees throughout the week, making this one of the most intense heat waves in recorded history.

Readings should not be quite as hot next week, but highs are expected to be in the 90s. The extreme dryness will also persist, but there is a chance we could see a few showers or a thunderstorm by late next week.

It’s not very common to report high temperatures over the 100-degree mark in June, but an intense heat wave like this one really is unprecedented. According to Cliff’s records, the earliest Coeur d’Alene has reported a temperature in the triple-digits was on June 22, 1973, when it was 101 degrees. Last year, we had one day when the mercury hit 100 degrees, which was on August 17.

Since the middle of June, it has been extremely hot across the western states. Death Valley, California, the site of the hottest world temperature of 134 degrees set back in 1913, hit 128 degrees on Thursday, June 17. That reading smashed its high for that date of 122 degrees. Many other locations in the deserts across the southwestern U.S. topped 110, and even 120 degrees over a week ago. On average, our hottest days are not too far away, so there is a chance that the all-time world record could be challenged in Death Valley.

The day of the all-time record 109-degree temperature in Coeur d’Alene was on August 4, 1961. On that particular afternoon, it was a very hot 108 degrees in Spokane. The Wenatchee airport hit 109 degrees, Ephrata and Lewiston, Idaho each observed an extremely hot 115 degrees. Pullman was 110, Colville was 107, Ritzville and the Spokane Valley reported 112 degrees, and Sandpoint, Idaho was 100 degrees.

One of the hottest summers was in 2017. During that season, we had 32 days with highs at or above 90 degrees, mostly in July and August. September 3, 2017, was the last day with a high temperature in the 90s in Coeur d’Alene. It was also very hot in 2015. At Cliff’s station, there were 16 days in a row with high temperatures at or above 90 degrees from June 25 through July 10, 2015. The mercury hit a record-breaking 105 degrees on June 28.

The most torrid summer season in our region in recorded history occurred in 1967. Cliff’s records indicate there was an all-time record 16 days that year with temperatures at or above 100 degrees and 45 days with readings at or above 90 degrees. During that year, the Spokane International Airport had 11 consecutive days with temperatures at 90 degrees or warmer. Lewiston, Idaho observed 11 consecutive days with readings at or above 100 degrees.

When air temperatures are hot, it can feel much hotter if humidity levels start climbing. The feels like summer temperatures are also known as a “heat index.” This was developed by R.I. Steadman of the National Weather Service back in 1979 and is calculated by combining air temperature and relative humidity. For example, a 90-degree temperature combined with a 90 percent relative humidity would push the heat index up to a very dangerous 122 degrees Fahrenheit. In the southwestern U.S., a 120-degree temperature often feels more like a dry heat as humidity levels are often very low.

Here in North Idaho, most of our very hot days typically have lower humidity values. Thanks to the Rocky Mountains, the humid air from the Gulf of Mexico is usually blocked from entering the far West.

However, temperatures over 100-degrees across the Inland Northwest are considered to be “dangerous” and we should carry plenty of water to stay hydrated. Depending on the age and health of individuals, prolonged exposure to heat index temperatures over 100 degrees can lead to sunstroke, heat exhaustion, muscle cramps and even heart attacks. Each year, approximately 600 people in the U.S. die from heatstroke.

The symptoms of heatstroke are when the body temperatures reach 103 degrees or higher. The skin is hot, red, dry or damp and there is a fast, strong pulse. Headaches, dizziness, nausea, confusion and passing out are classic signs of heatstroke. If someone is experiencing heatstroke, call 9-1-1 right away as it’s considered to be a medical emergency.

The person suffering from heatstroke should also be moved to a cooler place and try to lower their body temperature with cool cloths or a cold bath. If possible, use evaporation cooling techniques by misting cool water on the body while warm air is fanned. This will cause the water to evaporate and cool the skin. One of the most important things is to not give the person anything to drink.

Contact Randy Mann at randy@longrangeweather.com.