 Now, from your 24-hour weather station, here's Southern Iowa's most accurate forecast on Ottumwa Radio. I'm meteorologist Megan Mulford with a look at your forecast. 56 overnight under partly cloudy skies, east winds 5 to 10 miles an hour. Daytime highs approaching 75 Monday, slight chance of rain showers. Partly cloudy Monday night, chance for storms, lows dip down to about 66.