Johnston weather
At 10:00 PM local time it was mostly clear and 14°C (57°F). Light rain for 1 of the next 24 hours (under 1 mm/h, 0.4 mm total) — cloudy, but fine to be out. Best months for weather: May–Oct. Johnston sits 254 m (833 ft) above sea level, which keeps it cooler than the coast. Below: today's sky, the hour-by-hour rain chance and the 16-day forecast for Johnston, Iowa, United States.
Current conditions
- Clouds
- 43%
- Chance of rain
- 4%
- Rain
- 0.0 mm/h
Hourly Forecast
Light rain for 1 of the next 24 hours (under 1 mm/h, 0.4 mm total) — cloudy, but fine to be out
Daily Forecast
Best Time to Visit
Peak season May–OctOff season Nov–Mar
About Johnston weather
Is it raining in Johnston right now?
No. It’s mostly clear and 14° right now. Light rain for 1 of the next 24 hours (under 1 mm/h, 0.4 mm total) — cloudy, but fine to be out.
What’s the weather like in Johnston this week?
Over the next 7 days, expect highs of 12–21° and lows of 8–15°. Rain is likely on 3 of 7 days (Sunday, Monday, Tuesday). The driest day looks like Sunday.
Has it been raining in Johnston lately?
Barely. The past 7 days were mostly dry, with 0.5 mm of rain in total.
What should I pack for Johnston?
For the coming week, bring an umbrella or rain jacket and a warm layer for the evenings.
Johnston weather by month
When is the best time to visit Johnston?
Based on weather alone, the best time to visit Johnston is May–Oct, according to NASA's 2001–2025 climate averages. Nov–Mar tends to be the least pleasant. Average highs run from -1°C (30°F) in January to 31°C (87°F) in July.
What is the rainiest month in Johnston?
June is the wettest month, with about 130 mm (5.1 in) of rain on average. January is the driest, with about 23 mm (0.9 in).
What is the hottest month in Johnston?
July is the warmest, with average highs of 31°C (87°F) and lows of 19°C (66°F). January is the coolest, with highs of -1°C (30°F) and lows of -10°C (14°F).
Does Johnston have a rainy season?
Not a strong one. No month averages more than 150 mm of rain; the wettest is June at about 130 mm (5.1 in).
Sources: 2001–2025 monthly averages from NASA POWER (MERRA-2 reanalysis), forecast and current conditions from Open-Meteo. Page updated . How we rate months