nomadseason

September Weather in Redmond, United States

Last updated: June 24, 2025

In Redmond, United States, the average temperature in September hovers around 17°C (62°F), offering a mild climate for both residents and visitors. However, temperatures can vary significantly, with minimums dipping to -1°C (30°F) and peaking at an impressive 38°C (101°F). During this month, expect an average precipitation of 25 mm (1.0 in) spread over 4 days, while the air maintains an average humidity of 59%. Get ready for a month of dynamic weather in this vibrant destination!

September Temperature in Redmond

In September in Redmond, the average temperature is 17°C (62°F), with maximums reaching up to 38°C (101°F) and minimums dropping as low as -1°C (30°F). This variation in temperature makes it essential to pack for both warm and cool conditions while traveling.

September Weather in Redmond: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Redmond, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Redmond, September typically has an average temperature of 17°C (62°F), with highs reaching up to 38°C (101°F) and lows dropping to around -1°C (30°F).
JanFebMarAprMayJunJulAugSepOctNovDec353641485664737262494135
Data source: Temperature data for Redmond generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Redmond

In Redmond in September, the precipitation amount is 25 mm (1.0 in) over the course of 4 days.

September Precipitation Trends in Redmond

The chart displays monthly precipitation patterns in Redmond, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Redmond, September typically receives around 25 mm (1.0 inches) of precipitation spread over approximately 4 days.
JanFebMarAprMayJunJulAugSepOctNovDec6478485028154625355466
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Redmond

In Redmond in September humidity is 59%. With an average temperature of 17°C (62°F), this humidity feels like a refreshing but slightly sticky embrace, making travel enjoyable yet requiring a light layer to stay comfortable as you explore the surroundings.

September Average Humidity in Redmond

This chart illustrates the average monthly humidity levels in Redmond, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Redmond is approximately 59%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec86%87%86%85%80%82%79%63%59%78%88%88%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Redmond

In Redmond in September, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Redmond.

Maximum UV Index Levels in Redmond for September

The chart shows the monthly maximum UV Index (UVI) for Redmond in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Redmond typically reaches 8, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec346810101098632
Data source: Redmond September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

How September Weather in Redmond Compares to Other Months

Weather in Redmond varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Redmond, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Redmond, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather1°C (35°F)64 mm (2.5 inches)86%moderate
February Weather2°C (36°F)78 mm (3.1 inches)87%moderate
March Weather5°C (41°F)48 mm (1.9 inches)86%high
April Weather9°C (48°F)50 mm (2.0 inches)85%very high
May Weather13°C (56°F)28 mm (1.1 inches)80%very high
June Weather18°C (65°F)15 mm (0.6 inches)82%very high
July Weather23°C (73°F)4 mm (0.1 inches)78%very high
August Weather22°C (72°F)6 mm (0.2 inches)62%very high
September Weather17°C (62°F)25 mm (1.0 inches)59%very high
October Weather10°C (49°F)34 mm (1.4 inches)78%high
November Weather5°C (41°F)54 mm (2.1 inches)88%moderate
December Weather2°C (35°F)66 mm (2.6 inches)88%low

Compare Redmond's Climate with Cities Worldwide