Armstrong, IA Weather & Growing Conditions
Today
73°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely. Mostly cloudy. High near 73, with temperatures falling to around 70 in the afternoon. North northwest wind 7 to 14 mph, with gusts as high as 20 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 | 73°F | Showers And Thunderstorms Likely | 7 to 14 mph NNW | 73% |
| Tonight | 55°F | Chance Showers And Thunderstorms then Mostly Cloudy | 2 to 7 mph WNW | 30% |
| Wednesday | 75°F | Mostly Sunny | 3 mph NE | 1% |
| Wednesday Night | 54°F | Mostly Clear | 6 mph SSE | 1% |
| Thursday | 81°F | Sunny | 6 to 12 mph SSW | 1% |
| Thursday Night | 61°F | Mostly Clear | 12 mph S | 3% |
| Friday | 84°F | Sunny | 9 to 15 mph SSW | 13% |
| Friday Night | 64°F | Slight Chance Showers And Thunderstorms | 7 to 14 mph S | 21% |
| Saturday | 86°F | Sunny then Slight Chance Showers And Thunderstorms | 7 to 17 mph S | 16% |
| Saturday Night | 68°F | Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms | 13 to 17 mph ESE | 26% |
| Sunday | 85°F | Chance Showers And Thunderstorms then Mostly Sunny | 12 mph ESE | 26% |
| Sunday Night | 67°F | Slight Chance Showers And Thunderstorms | 9 to 13 mph E | 31% |
| Monday | 84°F | Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms | 13 to 16 mph E | 31% |
| Monday Night | 66°F | Slight Chance Showers And Thunderstorms | 10 to 16 mph NE | 31% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Armstrong, IA
Last spring frost
May 4
First fall frost
Oct 1
Growing season
150 days
Hardiness zone
5a
Explore more for Armstrong, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Swea City 5N, Ia (8.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.