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July 20, 2026 - Tornado Track Update

Current conditions at

Marshalltown, Marshalltown Municipal Airport (KMIW)

Lat: 42.11° N Lon: 92.92° W Elev: 971 ft.

Fair

61°F

16°C

Humidity	97%
Wind Speed	N 7 mph
Barometer	29.92 in (1012.6 mb)
Dewpoint	60°F (16°C)
Visibility	10.00 mi
Last update	2 Aug 4:53 am CDT

More Information:

Local Forecast Office More Local Wx 3 Day History Hourly Weather Forecast

Detailed forecast for

Grundy County

Rest Of Tonight

Mostly clear. Near steady temperature in the lower 60s. North winds around 5 mph.

Sunday

Mostly sunny. Humid with highs in the lower 80s. Northeast winds 5 to 10 mph.

Sunday Night

Partly cloudy in the evening, then becoming mostly clear. Lows around 60. East winds around 5 mph.

Monday

Mostly sunny. Highs in the lower 80s. Southeast winds 5 to 10 mph.

Monday Night

Mostly clear. Humid with lows in the lower 60s. South winds 5 to 10 mph.

Tuesday

Partly sunny. A slight chance of showers and thunderstorms in the afternoon. Highs in the lower 80s. Chance of rain 20 percent.

Tuesday Night

A chance of thunderstorms. Showers. Lows around 60. Chance of rain 80 percent.

Wednesday

Becoming partly sunny in the afternoon. A chance of thunderstorms. Showers likely, mainly in the morning. Highs in the mid 70s. Chance of rain 60 percent.

Wednesday Night

Mostly cloudy in the evening, then becoming partly cloudy. A 50 percent chance of showers. Lows in the upper 50s.

Thursday

Mostly sunny. Highs in the upper 70s.

Thursday Night

Mostly clear in the evening, then becoming partly cloudy. Lows around 60.

Friday

Mostly sunny. Highs in the lower 80s.

Friday Night

Mostly clear in the evening, then partly cloudy with a slight chance of showers and thunderstorms after midnight. Lows in the mid 60s. Chance of rain 20 percent.

Saturday

Mostly sunny. Highs in the mid 80s.