The calendar for Sunday’s 3M Half Marathon hadn’t changed, but the weather certainly did. Instead of the cool conditions that 3M typically enjoys which often necessitates gloves and hats, Sunday’s weather felt more like April or May with suffocating humidity, a light mist and temps in the mid-60s.

Nearly every runner in the sold-out field of nearly 6000 suffered in the unseasonably warm conditions.

Even the front-runners, who are usually immune to the more temperate conditions, had trouble in the thick air, and the winnings times were the slowest in years.

Still, 3M was dominated by the Africans, namely Kenyans Stephen Muange and Hirut Mendefro. Muange won the men’s division in 1:04:14, well off last year’s winning time of 1:03:22 (in much cool weather) and Mendefro won 3M for the second year in a row in 1:15:26, slightly more than a minute slower than her time in 2010.

Both times were surprisingly pedestrian on the lightning fast, north-to-south course and both winners attributed it to the weather. "I felt very warm," said Muange after winning a close duel with Girma Tolla (1:04:17). "The humidity was difficult for me."

Tolla and Muange both live in New Mexico and have raced each other numerous times although Tolla—an Ethiopian—has never beaten the Kenyan. "Today I thought I had a chance to win," said Tolla, "but the humidity was horrible."

Mendefro echoed those sentiments. "I am happy to have won," said the 25-year-old, "but I didn’t feel like I could push the pace this morning. The humidity was quite high."

Indeed. Although Muange had a tough battle with Tolla down the famed 3M hills all the way to the finish on Trinity, Mendefro was able to separate herself from Svetlana Demidenko of Russia at about the nine-mile mark and ran virtually by herself the last four miles. Demidenko, 34, was second in 1:15:01.

In the men’s race, Derese Deniboba placed third in 1:05:50 with Joseph Ngetich fourth in 1:06:13 and Sammy Kiplagat taking fifth in 1:06:19. First American was Christian Hesch of Morro Bay, California in eighth in 1:07:39.

First masters runner of the morning was the age-defying Paul Zimmerman. Now 50 and having moved from Cedar Creek to Phoenix, Zimmerman ran a superb time of 1:10:11. Second went to Oz Hofstatter, 40, of Cedar Park in 1:13:13.

Rounding out the top five women after Mendefro and Demidenko came Truphen Taurus Jemeli in third in 1:17:04. Finishing fourth was a familiar face: Chris Kimbrough. Now 41 and just beginning to get her feet wet in competitive racing after giving birth to her fifth child in January of 2010, Kimbrough ran 1:18:02 to place just ahead of McKale Davis of Stillwater, Oklahoma in 1:18:16.

Kimbrough, who hopes to qualify again for the US Olympic Marathon Trials, had an up-and-down race. "I ran well in the beginning," said Kimbrough who ran 1:15:30 at 3M in 2007. "I had a stitch and ran poorly in the middle but good at the end." The big thing for me was I enjoyed it."

Second masters woman was another familiar face who has been missing from the Austin racing scene for nearly three years: Lori Stich. Now living in Colorado Springs and remarried, Stich was pleased with her 1:22:15. "I like to run happy," said Stich, "and being in Austin, it’s easy to run that way."

Among the top runners one of the few who was pleased with her race was Liz Shelton of Buda. The former UT miler, Shelton had a game plan of running negative splits and stuck to it.

"When I saw how warm it was at the start," said Shelton who ran 1:22:49 for seventh, "I took that into account and made a conscious effort to hold back." Her time was only two minutes slower than her PR.

3M was the fourth of five races in the Austin Distance Challenge Series. Next up is the big enchilada: The Livestrong Austin Marathon on February 20th.