Storms, then sun drove dew point up to record levels -- 82, driving the heat index to 119 -- Tuesday, but relief is in sight.
Heat and humidity hit misery records in the Twin Cities Tuesday after a ferocious lunch-hour storm flooded streets and knocked down power lines. But there's good news: Only one day to go in Heat Wave 2011.
Wednesday will bring the fourth straight day with high temperatures in the upper 90s, and the fifth with some of the highest dew points in the nation -- perhaps the world. But a rollback to near normal temperatures Thursday will "probably feel pretty cool compared to what we've had," said National Weather Service meteorologist Chris Franks.
Meanwhile, some Twin Citians apparently already had adapted to the tropical conditions.
"I like the heat," said Minneapolis traffic control officer T. Gamble. Standing in the intersection of 7th Street and 1st Avenue N. amid a crush of commuters in a hurry to get home and Twins fans in a hurry to get to the evening game, Gamble was barely breaking a sweat. "I've been waiting for this all year long. In the winter, I'm bundled up like an Eskimo. I can't stand the cold."
On Nicollet Mall, hot dog vendors Patrick McCutchan and Audrey Ukena withstood the heat from both their steamer and the sun. A Florida native, Ukena loves the heat. "You just have to stay hydrated and love what you do," she said. Toward evening, their hot dogs weren't selling all that fast but water for a buck kept business steady.
The dew point
The dew point -- a measure increasingly regarded as summertime's chief standard for discomfort -- reached 82 at Minneapolis-St. Paul International Airport Tuesday afternoon, the highest mark since readings began in 1945. "You could say we're probably as warm as any place in the world right now," Franks said Tuesday afternoon. "It's quite miserable."
The day's high temperature of 95 was well below the record of 100, but the dew point drove the heat index, or "feels like" factor, to 119. That was another record, according to meteorologist Paul Douglas.
The "Extreme and Weird Weather of the World" website reported that Hallock, Minn., near the Canadian border, had the highest dew point on the globe at 86, but a meteorologist at the National Weather Service office in Grand Forks, N.D., said that reading was probably faulty.
The higher the dew point, the more difficult it is for the human body to shed heat through sweat and evaporation. July dew points in the Twin Cities can drop into the 40s, but customarily hit the high 50s and low 60s, Douglas said.
Only two people sought treatment at Hennepin County Medical Center Emergency room Tuesday for heat-related issues.
The heat and plentiful water vapor in the air fashioned a super-soaker thunderstorm that targeted the Twin Cities over the Tuesday noon hour.
Winds of nearly 60 miles per hour were reported to the National Weather Service all across the northern metro area, as well as 1-inch diameter hail. Lightning in Blaine halted soccer matches for about two hours at the Schwan's USA Cup Youth Tournament, organizers said.
St. Paul Fire Marshal Steve Zaccard said lightning struck a garage in the 700 block of N. Grotto Street about noon. Zaccard said there were also reports of downed power lines.
"Lightning strikes are not too common, but wires down, we get those all of the time," he said.
The most intense rain, which appeared to wheel directly over the heart of the metro area, dropped just short of an inch of rain in about 20 minutes near the Metrodome in downtown Minneapolis. Blaine recorded 1.13 inches.
The storm collapsed a steel building nearing completion at the county fairgrounds in Wadena, which was devastated by a tornado in June 2010. In Roseville, Fairview Avenue had at least 18 inches of water where it passes under Hwy. 36, according to the Weather Service. About 3,800 Xcel Energy electricity customers were without power across the metro area as of 11:30 a.m. In Minneapolis, midday skies were so dark prior to the storm that streetlights came on.
At the Star Tribune, the temperature dropped from 86 to 73 after the storm, then zoomed back to 85 by 2 p.m.
"Good, old-fashioned summertime thunderstorms," said Tom Hultquist, chief science officer of the Twin Cities office of the National Weather Service, describing the short but intense encounter. Radar indicated formations that often spawn tornadoes, but Hultquist said the storm was dropping so much water and extended so high in the atmosphere -- to nearly 65,000 feet -- that it prevented updrafts that might have generated a tornado.
Energy users trying to stay cool set a new record for demand in Minnesota and three neighboring states on Monday.
The state's largest utility also reported thousands of power outages. "It is not that there is not enough supply," spokesman Tom Hoen said. "It's from the demand and stress being put on the system.''
The utility expected high power demand to continue during the heat wave. About 3,000 customers across the metro area were without power Tuesday evening.
Hoen said the previous record was set last Aug. 9 at 9,100 megawatts (MW). By comparison, Xcel's largest power generation station, at Becker, Minn., puts out a total of 2,400 MW.
At the worst Monday, more than 8,000 customers lost power, but that was down to 1,700 on Tuesday morning. Xcel on Monday activated remote-controlled power-saving switches on air-conditioning units of residential customers who signed up for the conservation program. The conservation step, which cycles off customers' air-condition condensers, was activated for about an hour.
Wednesday is expected to bring a high of 94 and a heat index of 110 to the Twin Cities. Thursday's high will scale back to a near normal 86, with dew points in the low 60s.