September Weather in Grand Forks, Canada

Last updated: June 18, 2025

In September, the average temperature in Grand Forks, Canada hovers around 13°C (57°F). Be prepared for a range of temperatures, as it can drop to a chilly -1°C (31°F) or rise to a warm 32°C (90°F). During this month, expect 45 mm (1.8 in) of precipitation spread over 7 days, with an average humidity of 74%. Whether you’re basking in the warmth or bundled up against the cold, it's a month full of surprises!

September Temperature in Grand Forks

In September in Grand Forks, the average temperature is 13°C (57°F). The maximum can reach 32°C (90°F), and the minimum can be as low as -1°C (31°F). Be prepared for a wide range of temperatures when traveling during this time.

September Weather in Grand Forks: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Grand Forks, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Grand Forks, September typically has an average temperature of 13°C (57°F), with highs reaching up to 32°C (90°F) and lows dropping to around -1°C (31°F).
JanFebMarAprMayJunJulAugSepOctNovDec242334425360696756413325
Data source: Temperature data for Grand Forks generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Grand Forks

In Grand Forks in September, the precipitation amount is 45 mm (1.8 in) spread over a duration of 7 days.

September Precipitation Trends in Grand Forks

The chart displays monthly precipitation patterns in Grand Forks, 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 Grand Forks, September typically receives around 45 mm (1.8 inches) of precipitation spread over approximately 7 days.
JanFebMarAprMayJunJulAugSepOctNovDec745968696645131845597172
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Grand Forks

In Grand Forks in September humidity is 74%. With an average temperature of 13°C (57°F), this humidity feels like a blanket of moisture wrapping around you, making outdoor excursions less comfortable and adding a stickiness to the air that could quickly fatigue travelers.

September Average Humidity in Grand Forks

This chart illustrates the average monthly humidity levels in Grand Forks, 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 Grand Forks is approximately 74%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec90%91%89%86%82%81%84%75%74%85%88%93%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Grand Forks

In Grand Forks in September, the maximum UV index is 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more detailed information, you can check the Hourly UV Index in Grand Forks.

Maximum UV Index Levels in Grand Forks for September

The chart shows the monthly maximum UV Index (UVI) for Grand Forks 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 Grand Forks typically reaches 7, which falls under the high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec235799987421
Data source: Grand Forks 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 Grand Forks Compares to Other Months

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

This table compares monthly weather conditions in Grand Forks, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather-5°C (24°F)74 mm (2.9 inches)90%low
February Weather-5°C (24°F)59 mm (2.3 inches)91%moderate
March Weather1°C (34°F)68 mm (2.7 inches)89%moderate
April Weather5°C (42°F)69 mm (2.7 inches)85%high
May Weather12°C (53°F)66 mm (2.6 inches)82%very high
June Weather16°C (61°F)45 mm (1.8 inches)81%very high
July Weather20°C (69°F)13 mm (0.5 inches)84%very high
August Weather20°C (68°F)18 mm (0.7 inches)75%very high
September Weather13°C (57°F)45 mm (1.8 inches)74%high
October Weather5°C (42°F)59 mm (2.3 inches)85%moderate
November Weather0°C (33°F)71 mm (2.8 inches)88%low
December Weather-4°C (26°F)72 mm (2.8 inches)93%low

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