The calendar may say May, but the record-high temperatures proclaim July in much of Utah.
Wednesday's high temperature was 99 degrees in Salt Lake City — shattering the old record of 92, set in 1958.
"It's the hottest May day ever known," said Mark Eubank, KSL-TV's chief meteorologist. Such high temperatures are more typical of July than May, he said. "It's just phenomenal."
The average high for this week of the year is 75 degrees; Salt Lake City sizzled at 24 degrees above that.
Eubank also said Wednesday's temperature was the hottest ever so early in Salt Lake City, and its effect on snowpack is stunning. For example, Eubank said, there was some 40 inches of snow at Bald Mountain summit in the Uintas — 10,715 feet above sea level and Utah's highest paved road — on May 20 when it was plowed. As of Thursday — nine days later — there was only 1 inch left.
A 96-degree high on May 30, 2002, was the previous hottest-ever May day.
Another 19 Utah communities set high-temperature records Wednesday, according to the National Weather Service. Four others tied them. Hottest was Zion National Park with a 106-degree reading, eclipsing the old record of 103, set in 2000. Coolest was Alta at 74 — which still broke the old record of 72, set in 1974.
Other record highs were set in Brigham City (94), Logan (93), Provo-BYU (97), Springville (100), Tooele (95), Richfield (97) and Kanab (98).
Thursday's high in Salt Lake City is expected to hit 94 degrees, with a lot of clouds, and Friday is predicted at 92 degrees. Eubank said that means Salt Lake City will likely tie the record for the most 90-degree days in May at seven. There have been five 90 or higher degree May days so far this month. Saturday and Sunday are expected to be 85 degrees.
He believes the clear skies, the south breeze that prevented any cooler Great Salt Lake breezes and the high upper-level temperatures all contributed to Wednesday's record high. The current high-pressure system also is more typical of July than May.
A small low-pressure system may arrive Friday and offer some relief. However, Eubank also said this could cause some microbursts and dust storms around the Salt Lake area.
"When it gets this hot, it is so easy to build a thunderstorm," he said.
Overnight lows should gradually decrease from about 67 degrees Thursday night to 59 degrees Sunday evening.
Utah Power/PacifiCorp spokesman Dave Eskelsen said about 3,000 customers in the West Jordan area lost power from 3:30 to 4:45 p.m. Wednesday because of an equipment failure that was likely hot weather-related.
However, a four-hour afternoon outage in the Layton area was not weather-related and only affected 141 customers. Another outage in South Ogden covered a wide area but only lasted for 10 minutes and was construction-related.
"We managed pretty well today," he said. "It hasn't been too bad."
Utah Power is rushing to finish a few upgrades by June 30 — usually the start of such hot temperatures. These projects should better protect more vulnerable areas from outages, but many are now done.
Eskelsen advises homeowners to set their thermostats as high as possible while allowing people to still be comfortable.
He also said some cash incentives are available through dealerships on more efficient evaporative coolers and air conditioners.
E-mail: lynn@desnews.com