Keystone weather in September 2019

  • 23°C maximum daytime temperature in September in Keystone23
    23°C max day temperature
  • 9 hours of sunshine per day (68% of daylight hours) in September in Keystone9
    9 hours of sunshine per day
  • 8 days with some rainfall in September in Keystone8
    8 days with some rainfall
  • 6°C minimum night-time temperature in September in Keystone6
    6°C min night temperature
  • 12 hours of daylight per day in September in Keystone12
    12 hours of daylight per day
  • No heat & humidity in September in Keystone0
    No heat & humidity
  • 32 mm monthly rainfall in September in Keystone32
    32 mm of monthly rainfall
  • UV (maximum) index 6 (High) in September in Keystone6
    6 (High) UV index

Going to Keystone? Find the best month to visit Keystone based on the weather.

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Expect 23°C daytime maximum temperatures in the shade with on average 9 hours of sunshine per day in Keystone in September. Check more long-term weather averages for Keystone in September before you book your next holiday to South Dakota in 2019/2020.

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More about Keystone

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The September weather guide for Keystone, South Dakota shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

Metric (°C / mm)  |  Imperial (°F / inches)

Guide to Keystone weather in September

The average maximum daytime temperature in Keystone in September is a warm 23°C (73°F). The average night-time temperature is usually a cold 6°C (43°F). There are usually 9 hours of bright sunshine each day, which represents 68% of the 12 hours of daylight.

Expect 32mm (1.3 inches) of rainfall across the whole of September with 8 days with some rain falling. Maximum UV levels will be high (6 UV index) at midday when the skies are clear.

Keystone sunrise & sunset times for September 2019

Browse the sunrise & sunset times for Keystone in September 2019. Select a month to view Keystone sunrise & sunset times for the next twelve months.

JanFebMarAprMayJunJulAugSepOctNovDec

Date Sunrise times Sunset times
Sunday, 1st September 2019 06:17 19:30
Monday, 2nd September 2019 06:18 19:28
Tuesday, 3rd September 2019 06:19 19:26
Wednesday, 4th September 2019 06:20 19:24
Thursday, 5th September 2019 06:21 19:23
Friday, 6th September 2019 06:22 19:21
Saturday, 7th September 2019 06:24 19:19
Sunday, 8th September 2019 06:25 19:17
Monday, 9th September 2019 06:26 19:15
Tuesday, 10th September 2019 06:27 19:13
Wednesday, 11th September 2019 06:28 19:12
Thursday, 12th September 2019 06:29 19:10
Friday, 13th September 2019 06:30 19:08
Saturday, 14th September 2019 06:32 19:06
Sunday, 15th September 2019 06:33 19:04
Monday, 16th September 2019 06:34 19:02
Tuesday, 17th September 2019 06:35 19:01
Wednesday, 18th September 2019 06:36 18:59
Thursday, 19th September 2019 06:37 18:57
Friday, 20th September 2019 06:38 18:55
Saturday, 21st September 2019 06:40 18:53
Sunday, 22nd September 2019 06:41 18:51
Monday, 23rd September 2019 06:42 18:50
Tuesday, 24th September 2019 06:43 18:48
Wednesday, 25th September 2019 06:44 18:46
Thursday, 26th September 2019 06:45 18:44
Friday, 27th September 2019 06:46 18:42
Saturday, 28th September 2019 06:48 18:40
Sunday, 29th September 2019 06:49 18:38
Monday, 30th September 2019 06:50 18:37
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