Grafton, IA Weather & Growing Conditions
Today
72°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely. Mostly cloudy, with a high near 72. West northwest wind 7 to 10 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 72°F | Showers And Thunderstorms Likely | 7 to 10 mph WNW | 68% |
| Tonight | 56°F | Chance Showers And Thunderstorms | 3 to 7 mph NW | 47% |
| Wednesday | 72°F | Mostly Sunny | 3 mph N | 1% |
| Wednesday Night | 54°F | Mostly Clear | 2 mph SSW | 1% |
| Thursday | 77°F | Sunny | 1 to 7 mph SSW | 0% |
| Thursday Night | 59°F | Mostly Clear | 6 mph S | 1% |
| Friday | 81°F | Sunny | 6 to 13 mph S | 8% |
| Friday Night | 64°F | Slight Chance Showers And Thunderstorms | 7 to 12 mph S | 18% |
| Saturday | 83°F | Slight Chance Showers And Thunderstorms then Sunny | 6 to 10 mph S | 15% |
| Saturday Night | 67°F | Chance Showers And Thunderstorms | 13 mph SSW | 36% |
| Sunday | 83°F | Chance Showers And Thunderstorms | 10 mph S | 36% |
| Sunday Night | 66°F | Slight Chance Showers And Thunderstorms | 9 mph SSE | 34% |
| Monday | 82°F | Chance Showers And Thunderstorms | 12 mph E | 34% |
| Monday Night | 66°F | Slight Chance Showers And Thunderstorms | 10 mph NE | 37% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Grafton, IA
Last spring frost
May 4
First fall frost
Oct 4
Growing season
152 days
Hardiness zone
5a
Explore more for Grafton, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Northwood, Ia (10.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.