By O. Kay Henderson (Radio Iowa)

Some thermometers in western Iowa hit triple digits yesterday. National Weather Service meteorologist Alex Trellinger says the highest temperature reported to his office in Sioux Falls was 102, just south of Akron.

“We got one of our sites at Morris, which is in Sioux County, at 100 degrees,” he says, “and then Spencer hit 101.”

That was the temperature in Spencer at 5 p.m. It’s been 97 years since Spencer had a 101 degree day in September — and that 101 degree day back in 1925 was on September 4th.

Things warmed up quickly in Iowa yesterday, with temperatures soaring by 11 a.m. “We just got a much warmer air into the region out ahead of a cold front, which really helped to effect all of these much warmer temperatures here in our region,” Trellinger says, “especially considering the time of year here, the middle-to-end of September.”

Trellinger says drought conditions played a role in yesterday’s high temperatures in northwest Iowa, as the sun’s heat bore down on parched ground.

“When we’re not in a drought, the heat is also used to evaporate some of the moisture in the soil there, so it’s not as efficient as a heating mechanism when there’s moisure in the soil,” he says, “so by being very dry, that does set us up to being warmer than usual.”

Several other Iowa cities broke high temperature records Tuesday. Cedar Rapids hit 96 and that was also the record high in Lamoni. It reached 95 in Burlington. Des Moines hit 94 and it was 93 in Dubuque. Meteorologist Jim Lee of the National Weather Service office in metro Des Moines, who was tracking the records, says Waterloo hit 96 degrees.

“We were unseasonably hot, as any resident would tell you,” Lee says. “We had multiple parts of the state get well up into the mid to upper 90s.”

A triple digit temperature had not been recorded on a September 20th anywhere in Iowa for 69 years. “By a lot of measures not only did we break daily records, but to be this late in the year and get this hot maybe it not unprecedented, but very rare,” Lee says.

Today’s forecast? Highs in the 60s and 70s.

By Radio Iowa Contributor

Forecasters say Iowa will ride another weather rollercoaster this week with high temperatures tomorrow climbing into the low to mid-90s, but then a cool front will arrive and knock highs by Thursday into the 60s, with lows in the 40s.

Meteorologist Darren Clabo, who moderated the regional climate update for the National Weather Service, predicts another warm-up will soon follow with lesser chances of rain.  “Above-average temperatures are really expected over the next one to two weeks, combined with below-average precipitation,” Clabo says. “Kind of expecting more or less an upper level ridge to stick around, which should bring us warmer-than-average and drier-than-average conditions, which isn’t necessarily a bad thing going into the harvest season, folks will be able to get out in the fields.”

He says that same pattern may continue right into October.  “There are some pretty strong signals that warmer-than-average conditions will persist over the central part of the United States combined with below-average precipitation,” Clabo says. “October is a drier month so below-average precipitation on a normally average to dryish month to begin with doesn’t bode well for filling stock ponds and allowing our stream flow to increase.”

Clabo says the climate outlooks show the La Nina pattern hanging on into winter, for the third year in a row, which -could- mean a warmer-than-normal winter ahead for Iowa.