Bismarck Weather in September
Bismarck in September sees high temperatures, with highs around 23°C (73°F) and overnight lows of 8°C (46°F). Overall perfect conditions make it one of the better months to visit.
Rainfall in Bismarck in September
Climate statistics over the past 30 years suggest around 8 days of rain, with 44 mm (1.7 in) average for the month. Expect a fairly normal spread of rainfall this month, with no particular pattern of very heavy or very persistent showers.
Temperature in Bismarck in September
Bismarck in September has perfect weather. Days reach 23°C (73°F) and nights cool to 8°C (46°F). Overall, the month follows a fairly predictable daily temperature pattern. With overnight lows of 8°C (46°F), nights are cold. The cold air does make for deep, comfortable sleep if you have enough blankets.
Sunshine in Bismarck in September
Expect sunny days throughout the month, with an estimated 245 hours of sunshine. This makes it a pleasant time to visit Bismarck.If your ideal day consists of dry skies and pleasant temperatures, May, June, July, August and September typically offer the best circumstances for Bismarck.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Bismarck's climate page.
Bismarck Temperature in September
Min Temperature
8°C (46°F)
Max Temperature
23°C (73°F)
Chance of Rain
27%
Precipitation
44 mm (1.7 in)
Rainy days
8 days
Humidity
63%
Sunshine
245 hours
Percentage Sunshine
65%
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Bismarck typically drop from around 26°C (79°F) at the start of September to approximately 21°C (70°F) by the end. Nights are cool, with lows typically ranging from 5°C (41°F) to 12°C (54°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Bismarck in September
Browse day-by-day weather records for Bismarck spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Bismarck historical weather extremes in September
According to our 49 years of weather records for Bismarck, the following extremes were recorded between 1976 and 2025.
- The warmest day in September was on September 5, 2001, with a maximum of 39°C (102°F).
- The lowest overnight temperature recorded in September was -6°C (21°F) (September 22, 1995).
Best Places in the United States of America in September
Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in September →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Bismarck in September
Pleasant temperatures in September mean you can pack light but flexibel pieces. Think cotton t-shirts, comfortable walking shorts, and one warmer layer for evenings. A light sweater or denim jacket works well. Rain gear is recommended, you can expect wet weather on multiple days. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.What To Do in Bismarck in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Bismarck's climate page.
Temperature Rainfall Sunshine Humidity
See the full Bismarck climate overview or explore weather in the United States of America.
