Duncan (OK) Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Duncan, Oklahoma, United States of America. Long-term data from 1990 to 2020 was used to calculate these averages. Now, let's break down all the details for a clearer picture.

On average, Duncan receives a reasonable amount of rain/snowfall, with an annual precipitation of 881 mm (35 in). Despite this overall moderate level, the city experiences distinct dry season during certain months throughout the year, as illustrated in the precipitation charts below.

Monthly Precipitation Levels

The average number of days each month with precipitation (> 0.2 mm (0.01 in))

Significant seasonal changes in precipitation occur throughout the year. During the wettest month, May receives substantial rainfall, averaging 148 mm (5.8 in) of precipitation, recorded across 12 rainy days.

In contrast, the driest month, January brings less rainfall, with 27 mm (1.1 in) over 4 rainy days.

May, the wettest month, has a maximum daytime temperature of 27°C (81°F). During the driest month January you can expect a temperature of 12°C (54°F). For more detailed insights into the city's temperatures, visit our Duncan Temperature page.

Duncan's average annual precipitation is 881 mm (35 in). Let's compare this to some popular worldwide tourist destinations:

Chicago, USA, sees an annual precipitation of 1062 mm (42 in), with rain and snow contributing to its humid climate.

In Seoul, South Korea, the average annual precipitation is 1237 mm (49 in), with most rain falling during the summer monsoon season.

Perth, Australia, receives 565 mm (22 in) of rainfall annually, mostly during the winter months.

Kuala Lumpur, Malaysia, receives 2529 mm (100 in) of annual rainfall, characteristic of its equatorial tropical rainforest climate, with consistent rainfall throughout the year and peak months during March and November.

Precipitation amounts are measured using specific gauges installed at weather stations, collecting both rain and snow and any other type of precipitation. Rainfall is measured directly in millimeters, while that from snow and ice is obtained by melting it. Automated systems often incorporate heaters to make this easier.

Information from these stations is transmitted via Wi-Fi, satellite, GPS, or telephone connections to central monitoring networks. This information is immediately updated and integrated into weather models and forecasts.

The proximity of a location to a large body of water can significantly affect its rainfall patterns:

• Ocean Influence: Coastal regions typically receive more rainfall due to the presence of moisture-laden winds from the ocean. These regions tend to have more humid climates and experience more frequent precipitation, especially in winter.
• Continental Climates: Areas further from the sea, such as inland or continental regions, experience less frequent rainfall and more extreme seasonal variations in precipitation.

• The U.S. has a significant number of thunderstorms every year, with over 14.6 million taking place across the world annually.
• Approximately 70% of lightning bolts strike land rather than oceans.
• A storm named John was the longest-lasting Pacific tropical storm, continuing for 31 days. As it crossed the dateline twice, it changed status from a hurricane to a typhoon and back to a hurricane.

For more detailed information about Duncan (OK)'s weather, including sunshine hours, humidity levels, and temperature data, visit our Duncan (OK) Climate page.