Dallas (OR) Monthly Rainfall & Precipitation

This page shows both the average monthly rainfall and the number of rainy days in Dallas, Oregon, United States of America. These averages rely on historical data collected over 30 years, from 1990 to 2020. Now, let's break down all the details for a clearer picture.

Dallas has a relatively rain/snowy climate with high precipitation levels, averaging 1261 mm (50 in) of rain/snowfall annually. Despite the high annual total, it does experience a distinct dry and rainy season during certain months. Examine our detailed charts below to understand these seasonal patterns.

Monthly Precipitation Levels

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

Dallas can be quite wet during December, receiving approximately 256 mm (10 in) of precipitation over 21 rainy days.

In contrast July, experiences much drier conditions, with 7.3 mm (0.3 in) of rainfall, spread across 3 rainy days.

December, the wettest month, has a maximum daytime temperature of 7°C (45°F). The city receives 76 hours of sunshine in this period. During the driest month July you can expect a temperature of 28°C (82°F). For more detailed insights into the city's temperatures, visit our Dallas Temperature page.

Dallas's average annual precipitation is 1261 mm (50 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 Shanghai, China, the annual average precipitation is 1347 mm (53 in), with a humid subtropical climate.

In Tokyo, Japan, the average annual precipitation is 1528 mm (60 in), with significant summer rains due to typhoon season.

Ho Chi Minh City, Vietnam, receives 1955 mm (77 in) of annual rainfall, with a pronounced wet season from May to November, typical of its tropical monsoon climate.

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.

Climate change is affecting precipitation patterns worldwide, including Dallas (OR):

• Changing Rainfall Patterns: Global warming causes drastic changes in the patterns of rainfall. Some areas have been experiencing increased frequency and intensity of rainfall, while other areas experience longer dry spells or even droughts.
• Local Impacts: Many regions are experiencing heavier rainfall in the winter months and drier, hotter summers. This affects agriculture, water resources, and ecosystems.

• "Ginger" was the longest-lasting Atlantic tropical storm, which spun around the open ocean for 28 days in 1971.
• The world's largest snowflake was recorded in the Guinness Book of Records, at 38 cm (15 inches) wide and 20 cm (7.9 inches) thick. The snowflake fell at Fort Keogh, Montana, USA, on 28 January 1887.
• The greatest snowfall recorded was on Mt. Rainier, Washington State, USA, over 31.5 meters (103 feet) fell during the winter of 1972.

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