Duane Dailey
University of Missouri Extension

October 7, 2019

Temperatures didn't drop: September felt like August

COLUMBIA, Mo. - September weather acted like August in Missouri, says Pat Guinan, state climatologist with University of Missouri Extension. Several locations, mostly in southern Missouri, saw record-setting heat.

Daily high temperatures reached into 80- and 90-degree ranges.

Drawing attention are temperatures that didn't drop to seasonal lows at night. Lowest temperatures at night set record highs.

Preliminary data shows statewide average temperature for September was 74.7 degrees. That's 6.4 degrees above historic average.

The ranking may change slightly, but Missouri had its second-highest September temperature on record, Guinan says. It was warmest since 1931.

Missouri's minimum average temperature was 63.8 degrees. That's 7.4 degrees above average. The low temperatures for the month do set a state record.

Precipitation was more varied across the state in September. Above-average rain fell across northern and west-central counties. Below-average rains were recorded in central, east-central and southern areas.

Radar and ground gauges showed 5-7 inches of precipitation in some areas, Guinan says. However, areas in southwestern Missouri showed only 2 inches of precipitation. There were pockets across the south that received only half an inch of rain or less. That's unusual dryness, he adds.

Overall, state average rainfall was 3.58 inches, almost half an inch below long-term average.

September was driest month since April.

October brings concerns over first fall frost, Guinan notes.

Climatology shows first light frost of 32 degrees or lower in the northern quarter of Missouri and eastern Ozarks by mid-October, he says.

Central Missouri and western Ozarks expect light frost by Oct. 21. Urban areas stay warm a few days longer.

The Bootheel expects light freeze by the end of October or early November.

But so far this year Missouri hasn't had normal weather.

Sidebar: Missouri lowest and highest rainfalls

Missouri Lowest and Highest Rainfalls
  Station Name County
Rainfall (in.)
LowsAlton 1.7NNW Oregon 0.19
  Houston 5.0SE Texas 0.25
  Mountain Grove 14.0S Douglas 0.35
  Charleston 5S Mississippi0.43
  Dexter 0.6WNW Stoddard 0.51
HighsKirksville Airport Adair 11.34
  Princeton 1.4NNE Mercer 11.15
  Spickard 7W Grundy 10.76
  Stanberry 4.4NE Gentry 10.61
  Milan 1.2SW Sullivan 10.58