When to go · St. Charles
St. Charles in August
Great month. Inside St. Charles's best window: May–Oct.
Key facts
- Verdict
- Great
- Temperature
- 32°C (90°F)90°F (32°C) / 20°C (68°F)68°F (20°C)
- average high / low
- Rain days
- 8
- Crowds
- High
- United States overall
- Prices
- High
- United States overall
Verdict
Inside St. Charles's best window: May–Oct.
Is another month better than August?
No other month rates higher than August for St. Charles in this guide.
Weather in August
- St. CharlesHighs around 32 °C (90 °F), lows around 20 °C (68 °F), rain on about 8 daysHighs around 90 °F (32 °C), lows around 68 °F (20 °C), rain on about 8 days
Crowds and prices
- Crowds · United States overall
- High
- Prices · United States overall
- High
United States overall: Hot and busy; wildfire smoke in the West, hurricane peak begins in the Southeast.
High-price month: see what to book ahead.
Compare two months
Weather, crowds and prices for any two months in St. Charles, side by side.
Verdict
Aug: Great
May: Great
Daytime high
Aug: 32 °C (90 °F)90 °F (32 °C)
May: 25 °C (77 °F)77 °F (25 °C)
Night low
Aug: 20 °C (68 °F)68 °F (20 °C)
May: 13 °C (55 °F)55 °F (13 °C)
Rain days
Aug: 8 (better)
May: 10
Crowds
Aug: High
May: Medium
Prices
Aug: High
May: Medium
Festivals listed
Aug: 0
May: 1
August: Inside St. Charles's best window: May–Oct.
May: Inside St. Charles's best window: May–Oct.
St. Charles: figures are long-term averages from this guide, not a forecast.
What to pack
- Light, breathable clothes, a sun hat and sunscreen