Mason City, IA Weather & Growing Conditions
Overnight
64°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms. Mostly cloudy. Low around 64, with temperatures rising to around 67 overnight. South southwest wind around 8 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 64°F | Chance Showers And Thunderstorms | 8 mph SSW | 29% |
| Tuesday | 73°F | Showers And Thunderstorms Likely | 6 to 9 mph NW | 67% |
| Tuesday Night | 56°F | Chance Showers And Thunderstorms | 2 to 6 mph NW | 48% |
| Wednesday | 73°F | Mostly Sunny | 2 mph N | 2% |
| Wednesday Night | 53°F | Mostly Clear | 1 mph SE | 1% |
| Thursday | 78°F | Sunny | 1 to 5 mph SSW | 1% |
| Thursday Night | 59°F | Mostly Clear | 5 mph S | 1% |
| Friday | 81°F | Sunny | 3 to 10 mph S | 9% |
| Friday Night | 64°F | Slight Chance Showers And Thunderstorms | 8 mph S | 19% |
| Saturday | 84°F | Slight Chance Showers And Thunderstorms then Sunny | 5 to 9 mph S | 15% |
| Saturday Night | 68°F | Chance Showers And Thunderstorms | 8 to 12 mph SSW | 35% |
| Sunday | 84°F | Chance Showers And Thunderstorms then Mostly Sunny | 9 mph SSE | 35% |
| Sunday Night | 66°F | Slight Chance Showers And Thunderstorms | 8 mph SSE | 33% |
| Monday | 83°F | Chance Showers And Thunderstorms | 10 mph ESE | 33% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Mason City, IA
Last spring frost
Apr 29
First fall frost
Oct 7
Growing season
161 days
Hardiness zone
5a
Explore more for Mason City, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Mason City, Ia (0.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.