Best time to visit Keystone

Find the best time to visit Keystone and plan your perfect trip in 2025/2026. Get holiday inspiration, weather guides, travel advice and find great deals.

Keystone by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for South Dakota

Marriott discount code: Kids stay & eat for free

  • Kids stay & eat for free at Marriot Bonvoy
  • Destinations include Europe, Middle East & Africa
  • Valid for up to 2 adults & 2 kids aged up to 12
Show discount codeShow discount code ******ZJ6
Redeem Marriott discount code >>

View all Marriott offers

When is the best time to visit Keystone?

The best time to visit Keystone is June and August based on the following average weather conditions.

Maximum daytime temperature = 22 - 30°C [remove]
Daily hours of sunshine = 10 hours or more [remove]

Change the criteria to reflect your weather preferences.

Change criteria

Max Day Temperature (°C)

  • 1°C maximum daytime temperature in January in Keystone1
    Jan
  • 3°C maximum daytime temperature in February in Keystone3
    Feb
  • 7°C maximum daytime temperature in March in Keystone7
    Mar
  • 14°C maximum daytime temperature in April in Keystone14
    Apr
  • 19°C maximum daytime temperature in May in Keystone19
    May
  • 25°C maximum daytime temperature in June in Keystone25
    Jun
  • 29°C maximum daytime temperature in July in Keystone29
    Jul
  • 28°C maximum daytime temperature in August in Keystone28
    Aug
  • 23°C maximum daytime temperature in September in Keystone23
    Sep
  • 16°C maximum daytime temperature in October in Keystone16
    Oct
  • 7°C maximum daytime temperature in November in Keystone7
    Nov
  • 2°C maximum daytime temperature in December in Keystone2
    Dec

Hours of Sunshine (daily)

Which is the hottest month in Keystone?

The hottest time of year in Keystone is normally July. Expect maximum daytime temperatures to reach 29°C with moderate heat and humidity.

Which month has the most rain in Keystone?

In terms of rainfall, May is usually the wettest month in Keystone with 77mm on average. There are normally 12 days in May with some rain.

When is it sunniest in Keystone?

The sunniest time of year in Keystone is normally August with bright sunshine on average for 73% of daylight hours; that's 10 hours of sunshine per day.

Best time to visit

The weather guide for South Dakota (Keystone) shows long term weather averages processed from data supplied by CRU (University of East Anglia) & today's weather forecast provided by meteoblue. Find out more about our data sources.

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

Back to top

South Dakota travel features

Do you want to learn more about South Dakota? Read our latest features covering travel tips and insider destination guides on where to go and what to do in South Dakota.

We don't currently have any travel features on South Dakota. Discover more about holiday destinations around the world with this selection of general travel articles.

Back to top

Related posts

Popular travel offers

Explore holidays in the sun for less

More holidays

Airport parking

More parking

Airport lounges

More lounges

Back to Holiday Weather Top ^