Thayer, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Thayer, a city in Union County, Iowa.
This Afternoon
66°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely. Cloudy. High near 66, with temperatures falling to around 59 in the afternoon. North wind around 8 mph. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.
7-day forecast for Thayer
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 66°F | Showers And Thunderstorms Likely | 8 mph N | 71% |
| Tonight | 45°F | Rain Showers Likely then Cloudy | 9 to 13 mph NW | 67% |
| Wednesday | 52°F | Mostly Cloudy | 13 to 16 mph W | 11% |
| Wednesday Night | 42°F | Mostly Cloudy | 12 mph W | 8% |
| Thursday | 53°F | Chance Rain Showers | 10 mph WNW | 39% |
| Thursday Night | 40°F | Mostly Cloudy | 8 mph NNW | 12% |
| Friday | 52°F | Partly Sunny | 3 to 8 mph N | 5% |
| Friday Night | 34°F | Mostly Cloudy | 2 mph NNW | 0% |
| Saturday | 56°F | Mostly Sunny | 1 to 5 mph WSW | 2% |
| Saturday Night | 37°F | Mostly Clear | 5 mph W | 4% |
| Sunday | 62°F | Sunny | 6 mph W | 5% |
| Sunday Night | 40°F | Mostly Clear | 7 mph SW | 1% |
| Monday | 65°F | Sunny | 7 to 12 mph SW | 0% |
| Monday Night | 42°F | Mostly Clear | 7 mph WNW | 0% |
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 Nov 4, 2026.