Thayer, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Thayer, a city in Union County, Iowa.
Overnight
70°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 70. South southwest wind around 9 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for Thayer
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 70°F | Chance Showers And Thunderstorms | 9 mph SSW | 32% |
| Saturday | 82°F | Chance Showers And Thunderstorms | 7 to 10 mph WSW | 40% |
| Saturday Night | 63°F | Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 8 mph N | 61% |
| Sunday | 68°F | Showers And Thunderstorms Likely | 8 to 12 mph NNE | 60% |
| Sunday Night | 58°F | Showers And Thunderstorms Likely | 12 mph NE | 60% |
| Monday | 60°F | Rain Showers Likely | 10 mph NE | 61% |
| Monday Night | 53°F | Chance Rain Showers | 7 to 10 mph NE | 52% |
| Tuesday | 59°F | Mostly Cloudy | 9 mph NE | 12% |
| Tuesday Night | 48°F | Mostly Cloudy | 3 to 7 mph NE | 4% |
| Wednesday | 62°F | Mostly Sunny | 5 mph ENE | 2% |
| Wednesday Night | 51°F | Mostly Cloudy | 3 mph E | 5% |
| Thursday | 64°F | Slight Chance Rain Showers | 5 mph ESE | 17% |
| Thursday Night | 55°F | Slight Chance Rain Showers | 3 mph ESE | 16% |
| Friday | 66°F | Slight Chance Rain Showers | 2 to 6 mph ESE | 16% |
Forecast source: National Weather Service (api.weather.gov) for Thayer (41.029, -94.050). Updated through the day.
Growing snapshot for Thayer
Last spring frost
Apr 23
First fall frost
Oct 17
Growing season
176 days
Hardiness zone
5b
More local growing data for Thayer: nearby ZIP 50254 weather · frost dates · planting calendar · Iowa frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Beaconsfield, Ia (12.8 mi from Thayer). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.