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Weather in Keystone in September 2019
- 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 2019/2020.
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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 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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