Missouri’s June temperatures were the warmest on average since 1953, according to a University of Missouri climatologist.

“You have to go back 57 years to find a warmer June,” said Pat Guinan with the MU Extension Commercial Agriculture program. Temperatures ran 4 to 6 degrees above normal over much of the state, with temperatures 6 to 7 degrees warmer in southeast Missouri.

“Preliminary data shows the month of June will be the seventh warmest in 116 years of weather records,” Guinan told MU Extension plant science specialists in a weekly teleconference. “Southeast Missouri will probably have its first- or second-warmest June ever.”

June rainfall records are the extremes, Guinan said. “North Missouri was extremely wet while south Missouri was extremely dry. The weather station at Bloomfield recorded zero rainfall the whole month. Lack of rain in June is highly unusual.”

At the same time, counties along the Iowa state line had almost three times their average rainfall for June. Official rain gauges topped 13 inches in Mercer County while over 14 inches fell at Kahoka, Mo., in Clark County adjoining Iowa and Illinois.

High rainfall levels caused repeated flooding of crop fields along streams and rivers across north Missouri. “Some fields have been underwater four times. Now they may be flooded again,” said Bill Wiebold, MU Extension crops specialist.

Chances for flooding will persist at least though the first half of July, Guinan said. The monthly outlook released July 1 by the Climate Prediction Center indicated temperatures would be below normal while rainfall would be above normal.

“Look for July to be cooler and wetter than normal, at least during the first half of the month,” Guinan said.

Guinan said reports from Crowley Ridge in southeast Missouri, where there is little irrigation, indicate corn yields have already been cut by half.

Wiebold said the local nature of weather impacts from flooding or drought can reduce yields to zero while not dropping the overall state corn-yield average.