Harlan (IA) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Harlan.
Climate overview of Harlan
Temperatures in Harlan, Iowa, United States of America, vary greatly throughout the year. July is the hottest month at 29°C (84°F), while January is the coldest at -1°C (30°F).
With around 958 mm (38 in) of annual rain/snowfall, the city has moderate precipitation levels. August is the wettest month and January the driest. It also has a distinct dry season from January to March, with warm summers and very cold winters. July is the sunniest month, averaging 11.2 hours of sunshine per day.
Harlan Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Harlan - and find the best time to visit.
Monthly Temperature in Harlan
The climate in Harlan is known for significant temperature differences throughout the year, making the weather dynamic. Typically, average maximum daytime temperatures range from a comfortable 29°C (84°F) in July to a very cold -1°C (30°F) in the coolest month, January.
Nights vary from 17°C (63°F) in July to around -12°C (10°F) during the colder months.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Harlan
Generally, Harlan receives mid-range precipitation levels, with 958 mm (38 in) annually. The climate in Harlan shows significant variation throughout the year. Expect high rainfall in August, the wettest month, with an average of 154 mm (6.1 in) of precipitation over 12 rainy days.
In contrast, the driest month January offers drier and sunnier days, with around 17 mm (0.7 in) of snowfall over 5 snowy days. For more details, please visit our Harlan Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Sunshine Hours in Harlan
For those who appreciate different seasons, Harlan serves as an ideal destination. Expect longer, more sun-filled days in July with an average of 11.2 hours of sunshine daily, and embrace the darker days in December, offering only 4.4 hours of daily sunlight.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Humidity in Harlan by Month
The relative humidity is high throughout the year in Harlan.
The city experiences its highest humidity in January, reaching 71%. In April, the humidity drops to its lowest level at 60%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Best Time to Visit Harlan
Each month is rated for comfortable sightseeing weather — mild temperatures and low rainfall. Tap a month for its full averages; your ideal time may differ for a beach or winter trip (see below).
- Best overall: July
- Warmest weather: June, July and August
- Most sunshine: July
- Fewest rainy days: January, November and December
- Wettest period: April, May, June, July, August and September, when rainfall peaks.
- Climate seasons: a distinct dry season from January to March, with warm summers and very cold winters
- Best for winter weather: January, with freezing nights around -12°C (10°F).
Frequently asked questions about the climate in Harlan
What is the best time to visit Harlan?
July typically offers the most optimal weather in Harlan. In contrast, January, February, March and December tend to have less optimal conditions. Harlan has a distinct dry season from January to March, with warm summers and very cold winters.
What temperatures can I expect in Harlan?
Daytime highs range from -1°C (30°F) in January to 29°C (84°F) in July. Nighttime lows range from -12°C (10°F) to 17°C (63°F). Temperatures vary considerably through the year.
How much rain does Harlan get?
Annual rainfall is around 958 mm (38 in). August is the wettest month with 154 mm (6.1 in), while January is the driest with 17 mm (0.7 in).
How sunny is Harlan?
Harlan receives around 2,736 hours of sunshine per year. July is the sunniest month with 335 hours, while December is the cloudiest with just 133 hours. Overall, Harlan enjoys abundant sunshine.
Harlan 3-Day Forecast
Harlan (IA) 3-Day Forecast
Harlan on the map
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