Harpers Ferry, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Harpers Ferry, a city in Allamakee County, Iowa.
Today
70°F
Showers And Thunderstorms
Showers and thunderstorms. Cloudy. High near 70, with temperatures falling to around 67 in the afternoon. Southeast wind around 3 mph. Chance of precipitation is 90%. New rainfall amounts between three quarters and one inch possible.
7-day forecast for Harpers Ferry
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 70°F | Showers And Thunderstorms | 3 mph SE | 85% |
| Tonight | 57°F | Showers And Thunderstorms Likely | 5 mph N | 73% |
| Sunday | 66°F | Chance Rain Showers then Mostly Cloudy | 6 to 9 mph NE | 34% |
| Sunday Night | 51°F | Mostly Cloudy | 8 mph NE | 14% |
| Monday | 65°F | Slight Chance Rain Showers | 5 to 8 mph NE | 19% |
| Monday Night | 46°F | Mostly Cloudy | 2 to 7 mph NE | 11% |
| Tuesday | 64°F | Mostly Sunny | 2 to 6 mph NE | 11% |
| Tuesday Night | 44°F | Partly Cloudy | 0 to 3 mph NE | 2% |
| Wednesday | 68°F | Sunny | 3 mph NE | 1% |
| Wednesday Night | 48°F | Mostly Clear | 2 mph NE | 3% |
| Thursday | 69°F | Mostly Sunny | 2 mph NE | 6% |
| Thursday Night | 50°F | Partly Cloudy | 1 mph NE | 2% |
| Friday | 72°F | Mostly Sunny | 2 mph E | 3% |
| Friday Night | 51°F | Partly Cloudy | 1 mph NE | 3% |
Forecast source: National Weather Service (api.weather.gov) for Harpers Ferry (43.201, -91.152). Updated through the day.
Growing snapshot for Harpers Ferry
Last spring frost
Apr 24
First fall frost
Oct 17
Growing season
175 days
Hardiness zone
5a
More local growing data for Harpers Ferry: nearby ZIP 52146 weather · frost dates · planting calendar · Iowa frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Lynxville Dam 9, Wi (5.9 mi from Harpers Ferry). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.