Thayer, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Thayer, a city in Union County, Iowa.
Today
86°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms. Partly sunny. High near 86, with temperatures falling to around 83 in the afternoon. North wind 6 to 9 mph. Chance of precipitation is 40%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for Thayer
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 86°F | Chance Showers And Thunderstorms | 6 to 9 mph N | 36% |
| Tonight | 63°F | Showers And Thunderstorms | 7 to 10 mph NNE | 84% |
| Wednesday | 73°F | Chance Showers And Thunderstorms then Showers And Thunderstorms | 9 mph NE | 77% |
| Wednesday Night | 59°F | Chance Showers And Thunderstorms | 3 to 9 mph NE | 45% |
| Thursday | 81°F | Mostly Sunny | 5 mph ENE | 10% |
| Thursday Night | 62°F | Mostly Clear | 3 mph SE | 5% |
| Friday | 86°F | Mostly Sunny | 3 to 7 mph S | 5% |
| Friday Night | 67°F | Mostly Clear | 6 mph S | 11% |
| Saturday | 90°F | Sunny | 5 to 12 mph SSW | 3% |
| Saturday Night | 72°F | Mostly Clear | 10 to 14 mph S | 9% |
| Sunday | 91°F | Mostly Sunny | 10 to 14 mph SSW | 9% |
| Sunday Night | 71°F | Partly Cloudy then Slight Chance Showers And Thunderstorms | 14 mph S | 19% |
| Monday | 92°F | Slight Chance Showers And Thunderstorms then Mostly Sunny | 12 to 15 mph SSW | 19% |
| Monday Night | 73°F | Slight Chance Showers And Thunderstorms | 12 to 15 mph S | 24% |
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 Aug 4, 2026.