Duncan (OK) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Duncan.
Climate overview of Duncan
The climate in Duncan, Oklahoma, United States of America, is marked by large temperature swings across the seasons, ranging from 36°C (97°F) in August to 11°C (52°F) in December.
Annual rain/snowfall is moderate at around 881 mm (35 in), with May being the wettest month. The city also has a distinct dry season from January to February, with very hot summers and cold winters.
Duncan Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Duncan - and find the best time to visit.
Monthly Temperature in Duncan
In Duncan, temperatures differ significantly between summer and winter months. Average daytime temperatures reach a very hot 36°C (97°F) in August. In December, the coolest month of the year, temperatures drop to a chilly 11°C (52°F).
At night, temperatures range from around 22°C (72°F) in August to -2°C (28°F) in December.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Duncan
On average, Duncan receives a reasonable amount of rain/snowfall, with an annual precipitation of 881 mm (35 in). Duncan can be quite wet during May, receiving approximately 148 mm (5.8 in) of precipitation over 12 rainy days.
In contrast, during the driest month (January), you will experience much drier conditions, with 27 mm (1.1 in) of precipitation spread across 4 rainy days. For more details, please visit our Duncan Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Best Time to Visit Duncan
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
- Best overall: April and October
- Warmest weather: July and August
- Wettest months: April, May and June, when rainfall is highest.
- Seasonal pattern: A distinct dry season from January to February, with very hot summers and cold winters
- Coldest conditions: December, with freezing nights around -2°C (28°F).
Frequently asked questions about the climate in Duncan
What is the best time to visit Duncan?
April and October typically offer the most optimal weather in Duncan. In contrast, July and August tend to have less optimal conditions. Duncan has a distinct dry season from January to February, with very hot summers and cold winters.
What temperatures can I expect in Duncan?
Daytime highs range from 11°C (52°F) in December to 36°C (97°F) in August. Nighttime lows range from -2°C (28°F) to 22°C (72°F). Temperatures vary considerably through the year.
How much rain does Duncan get?
Annual rainfall is around 881 mm (35 in). May is the wettest month with 148 mm (5.8 in), while January is the driest with 27 mm (1.1 in).
Duncan 3-Day Forecast
Duncan on the map
Duncan is highlighted - select any city to see its climate.
Popular this month
Where to go in August - average daytime high across popular destinations.
Kissimmee
33°C (91°F) Orlando33°C (91°F) Miami Beach32°C (90°F) Destin32°C (90°F) New York City
29°C (84°F) Big Bear Lake
27°C (81°F) Los Angeles
24°C (75°F) San Francisco22°C (72°F) 
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