10-Day Weather Forecast - Johnston, IA

Partly sunny. Highs in the upper 70s. Northwest winds around 5 mph.

Mostly cloudy. A slight chance of showers after midnight. Lows in the lower 60s. East winds around 5 mph. Chance of rain 20 percent.

Partly sunny. A slight chance of showers in the morning. Highs in the upper 70s. East winds 5 to 10 mph with gusts up to 20 mph. Chance of rain 20 percent.

Mostly cloudy. Lows in the lower 60s. East winds 5 to 10 mph.

Partly sunny. Highs in the mid 80s.

Mostly cloudy in the evening then becoming partly cloudy. A slight chance of showers and thunderstorms. Lows in the lower 70s. Chance of rain 20 percent.

Sunny. A slight chance of showers and thunderstorms in the morning. Breezy with highs in the lower 90s. Chance of rain 20 percent. Heat index values up to 105 in the afternoon.

Mostly clear. Lows in the mid 70s. Heat index values up to 100 early in the evening.

Sunny breezy hot with highs in the mid 90s. Heat index values up to 105.

Mostly clear with a slight chance of showers and thunderstorms in the evening then partly cloudy with a chance of showers and thunderstorms after midnight. Breezy with lows in the mid 70s. Chance of rain 30 percent. Heat index values up to 100 early in the evening.

Sunny with a slight chance of showers and thunderstorms. Highs in the mid 90s. Chance of rain 20 percent. Heat index values up to 100.

Partly cloudy with a chance of showers. A slight chance of thunderstorms in the evening then a chance of thunderstorms after midnight. Lows in the lower 70s. Chance of rain 50 percent.

Mostly sunny. Highs in the mid 90s. Heat index values up to 100.

Clear with a 25% chance for rain and thunderstorms. Low temperature around 77F. Dew point will be around 72F with an average humidity of 72%. Winds will be 9 mph from the S.

Sunny. High temperature around 95F. Dew point will be around 71F with an average humidity of 59%. Winds will be 9 mph from the S.

Clear with a 30% chance for rain and thunderstorms. Low temperature around 76F. Dew point will be around 71F with an average humidity of 71%. Winds will be 7 mph from the S.

Sunny with a 40% chance for rain and thunderstorms. High temperature around 94F. Dew point will be around 71F with an average humidity of 60%. Winds will be 7 mph from the S.

Clear with a 35% chance for rain and thunderstorms. Low temperature around 74F. Dew point will be around 70F with an average humidity of 72%. Winds will be 5 mph from the SW.