Gale-force winds slammed through many areas of Utah Thursday, causing long power outages, dust clouds, traffic accidents and a multitude of other problems.
Cannonville, Garfield County, received .75 of an inch of precipitation in 23 minutes from the "microburst" storm. Several other areas, including Kanab, received moisture.William J. Alder, meteorologist in charge of the Salt Lake office of the National Weather Service, said there's still enough moisture in the air for some widely scattered afternoon and evening thundershowers Friday, but a general drying trend is forecast for the weekend.
Blackouts were reported from Holladay to Capitol Hill and from Parleys Canyon to the downtown area as winds roared through the Salt Lake Valley during Thursday's rush-hour traffic.
Wind gusts as high as 70 mph were clocked in the northern part of Lake Powell and gusts in excess of 60 mph were recorded alllong the Wasatch Front.
Dave Mead, Utah Power & Light Co. spokesman, reported at 10 a.m. Friday that there were still one or two isolated power outages in the Salt Lake Valley.
"The varmints were lightning and wind - particularly wind. We may have taken a lightning hit or two" near a downtown substation, he said.
Thousands of Salt Lake Valley homes were without power, some for six hours Thursday afternoon and evening, while linemen repaired major feeder lines.
Mead said there were 200 to 300 powerline crewmen out at the height of the storm, many of whom worked through the night to restore power to UP&L customers.
Downed power lines also snarled traffic as officers were needed to route motorists through intersections left black by the outages.
Alder said an area of microburst thunderstorms started building in southwest Utah about mid-morning Thursday and gathered strength as they moved north and east.
"There was a very organized area of thunderstorm cells. They usually aren't that organized but more spotty. It created a tremendous area of microbursts - like a gust front," Alder said.
Microbursts, strong, localized winds associated with downdrafts from thunderstorms, are most apt to occur when rain begins falling at the 12,000 to 14,000-foot elevation, then evaporates as it hits the ground. Localized areas of strong winds usually develop, Alder said.
Besides the strong winds, lightning crisscrossed the skies in many areas. In a three-hour period, between 10:15 a.m. and 1:15 p.m., there were 1,500 cloud-to-ground lightning strikes in an area bounded by Delta, Richfield, Bryce Canyon, Kanab, St. George and west of Ely, Nev. That is only one-third the number of strikes that normally occur.
A lightning strike sparked a grass fire at an illegal dump at 12th West and South Temple, according to a Salt Lake City Fire Department dispatcher.
Other precipitation amounts from the microburst storms Thursday:
Kanab, .28 of an inch; Provo and Brigham Young University, .11; East Mill Creek and Sandy, .15; Holladay, .03; and the Salt Lake Airport, trace.
The temperature Friday along the Wasatch Front is expected to be in the upper 80s, but will probably rise to the low 90s by Sunday. It will be about 10 degrees warmer in southern Utah.
The normal temperature for this time of year is 91 degrees. "As of Friday, we are running a degree below normal this month," Alder said.