O'Fallon Weather in December

December in O'Fallon brings low temperatures, with daytime highs of 7°C (45°F) and nights around -3°C (27°F). Quite a bit of snow/rainfall is expected, around 95 mm (3.7 in), so pack an umbrella.

Rainfall in O'Fallon in December

Typically around 11 days of snow/rainfall are expected, averaging 95 mm (3.7 in) for the month. When it rains this month, it tends to come down fairly heavily. Showers can be substantial even if they don't last all day.

Temperature in O'Fallon in December

December in O'Fallon brings low temperatures, with highs of 7°C (45°F) and nights around -3°C (27°F). During December, you'll experience the winter season. Expect a cold feel throughout the day, not just in the mornings and evenings. Warm layers are essential. Nights are well below freezing at -3°C (27°F). An extra blanket is a good idea if you feel the cold, especially in older or less well-heated accommodation.

Sunshine in O'Fallon in December

The area enjoys a balanced 128 hours of sunlight, ensuring it's neither too overcast nor too sunny.

December in O'Fallon can still be great, but if you prefer pleasant temperatures along with dry and sunny conditions, our weather planner can help you explore other options in the world.