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Weather in Keystone in September 2018
- 23°C max day temperature
23 - 9 hours of sunshine per day
9 - 8 days with some rainfall
8 - 6°C min night temperature
6 - 12 hours of daylight per day
12 - No heat & humidity
0 - 32 mm of monthly rainfall
32 - 6 (High) UV index
6
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 2018/2019.
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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 2018
Browse the sunrise & sunset times for Keystone in September 2018. Select a month to view Keystone sunrise & sunset times for the next twelve months.
JanFebMarAprMayJunJulAugSepOctNovDec
| Date | Sunrise times | Sunset times |
|---|---|---|
| Saturday, 1st September 2018 | 06:17 | 19:29 |
| Sunday, 2nd September 2018 | 06:18 | 19:27 |
| Monday, 3rd September 2018 | 06:19 | 19:26 |
| Tuesday, 4th September 2018 | 06:20 | 19:24 |
| Wednesday, 5th September 2018 | 06:22 | 19:22 |
| Thursday, 6th September 2018 | 06:23 | 19:20 |
| Friday, 7th September 2018 | 06:24 | 19:18 |
| Saturday, 8th September 2018 | 06:25 | 19:17 |
| Sunday, 9th September 2018 | 06:26 | 19:15 |
| Monday, 10th September 2018 | 06:27 | 19:13 |
| Tuesday, 11th September 2018 | 06:28 | 19:11 |
| Wednesday, 12th September 2018 | 06:30 | 19:09 |
| Thursday, 13th September 2018 | 06:31 | 19:08 |
| Friday, 14th September 2018 | 06:32 | 19:06 |
| Saturday, 15th September 2018 | 06:33 | 19:04 |
| Sunday, 16th September 2018 | 06:34 | 19:02 |
| Monday, 17th September 2018 | 06:35 | 19:00 |
| Tuesday, 18th September 2018 | 06:36 | 18:58 |
| Wednesday, 19th September 2018 | 06:38 | 18:56 |
| Thursday, 20th September 2018 | 06:39 | 18:55 |
| Friday, 21st September 2018 | 06:40 | 18:53 |
| Saturday, 22nd September 2018 | 06:41 | 18:51 |
| Sunday, 23rd September 2018 | 06:42 | 18:49 |
| Monday, 24th September 2018 | 06:43 | 18:47 |
| Tuesday, 25th September 2018 | 06:44 | 18:45 |
| Wednesday, 26th September 2018 | 06:46 | 18:44 |
| Thursday, 27th September 2018 | 06:47 | 18:42 |
| Friday, 28th September 2018 | 06:48 | 18:40 |
| Saturday, 29th September 2018 | 06:49 | 18:38 |
| Sunday, 30th September 2018 | 06:50 | 18:36 |
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