Even by desert standards, the heatwave in the Southwest is atypical. Tuscon’s National Weather Service (NWS) on Thursday tweeted that the city recorded a temperature of 100 degrees at 8:14 a.m. – the second earliest hour of the day on record since 1948.
It was only slightly later than the first recorded hour of reaching 100 degrees, which was in 2017, June 20, when Tucson hit 100 degrees at 8:02 a.m. The maximum that day was 116 degrees. Phoenix’s record temperature of 122 degrees occurred on June 26, 1990.
The high heat so early in the day has reinforced the need for the excessive heat warnings that have been in place throughout the week in Arizona, Nevada, Utah and California.
On Friday morning, Phoenix recorded a low temperature – yes, a LOW temperature – of 92. This is a problem, as it does not allow the body to cool down successfully at night.
The temperature must drop to at least 80 degrees for recovery to begin. In fact, a person can lose up to 2 liters of fluid overnight through sweating if the temperature never drops below 85 degrees.
Half a dozen western states will have low morning temperatures between 10 and 20 degrees above normal until Sunday.
The National Weather Service issues heat advisories and warnings with safety being their top priority.
Heat is the leading cause of weather-related death in the United States, and provides advice on the likelihood of heat-related illnesses – including heat cramps, heat exhaustion, stroke and possibly death – helps protect the public in extreme heat.
Many heat records are broken
Record temperatures have spread from California to Montana this week. Palm Springs, Calif., Tied the all-time highest temperature on Thursday at 123 degrees, breaking June’s previous record of 122 degrees.
Salt Lake City also tied its record 107 degrees. The old record was notably set in July, when temperatures are generally at the highest of the year in this region. It comes after daily records were broken Sunday, Monday and Tuesday in Salt Lake, each with temperatures exceeding 100 degrees.
Records are kept for all-weather highs (and lows), and also record high or low temperatures for specific months.
Death Valley, Calif., Broke its record daily temperature record for Thursday at 128 degrees – the previous record was 122 degrees set in 1917 – and was only one degree away from matching June’s record. The hottest temperature recorded in Death Valley was 134 degrees in July 1913.
Las Vegas set two daily records this week after dropping one degree less than its all-time high of 117 degrees on Wednesday.
Record temperatures in Pueblo, Colorado Springs and Alamosa, Colorado were also set yesterday. Thursday was the first day on record in Colorado Springs to hit 100 degrees.
Denver also hit 100 degrees on Thursday, marking only the 6th time in history that they have hit 100 degrees on three or more consecutive days.
The weekend remains hot for the West
Temperatures will remain 10 to 20 degrees above average throughout the weekend for much of the west.
The good news is that the heat will start to subside by the start of next week in the Southwest. The heat also drops a bit in the Pacific Northwest on Wednesday.
However, as we are only two weeks into the meteorological summer, long term cooler temperatures are not expected for some time.