Harpers Ferry, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Harpers Ferry, a city in Allamakee County, Iowa.
This Afternoon
70°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 5pm, then showers and thunderstorms likely. Cloudy. High near 70, with temperatures falling to around 66 in the afternoon. East wind around 3 mph. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.
7-day forecast for Harpers Ferry
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 70°F | Chance Showers And Thunderstorms | 3 mph E | 55% |
| Tonight | 57°F | Showers And Thunderstorms Likely | 6 mph NE | 67% |
| Sunday | 71°F | Slight Chance Rain Showers then Mostly Cloudy | 9 mph NE | 22% |
| Sunday Night | 51°F | Mostly Cloudy | 5 to 8 mph NE | 11% |
| Monday | 65°F | Chance Rain Showers | 7 mph NE | 49% |
| Monday Night | 48°F | Chance Rain Showers | 2 to 6 mph NE | 49% |
| Tuesday | 64°F | Slight Chance Rain Showers then Partly Sunny | 2 to 6 mph NE | 16% |
| Tuesday Night | 45°F | Partly Cloudy | 1 to 5 mph NE | 3% |
| Wednesday | 67°F | Mostly Sunny | 3 mph NE | 2% |
| Wednesday Night | 49°F | Partly Cloudy | 2 mph NE | 0% |
| Thursday | 69°F | Partly Sunny then Slight Chance Rain Showers | 1 mph E | 15% |
| Thursday Night | 53°F | Slight Chance Rain Showers then Mostly Cloudy | 0 mph | 15% |
| Friday | 73°F | Partly Sunny | 1 mph NE | 5% |
| Friday Night | 53°F | Partly Cloudy | 0 mph | 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.