O'Fallon Weather in January

O'Fallon in January sees low daytime temperatures of 5°C (41°F) and nighttime lows of -6°C (21°F). With just 44 mm (1.7 in) of snow/rainfall on average, it's the driest month of the year.

Rainfall in O'Fallon in January

This month sees the least rain of the year, making it well suited for outdoor adventures, even if you'll need a jacket. Historically, approximately 7 days this month are expected to have snow/rain, averaging 44 mm (1.7 in). A fairly balanced picture this month, some wet days but nothing too extreme in terms of intensity.

Temperature in O'Fallon in January

Daytime temperatures in O'Fallon reach 5°C (41°F) in January, dropping to -6°C (21°F) at night. January is known for being in the winter season. Expect a distinctly cold feel throughout the day, not just overnight. At -6°C (21°F) overnight, frost and ice are likely outside. Indoors, consider packing an extra blanket if you're unsure about the heating. This month tends to bring the coldest weather of the year, so be sure to pack enough warm clothing to stay comfortable.

Sunshine in O'Fallon in January

The month brings about 163 hours of sunlight, offering a comfortable mix of sun and overcast.

If you're looking for dry conditions and comfortable temperatures, January may not be the ideal month to visit O'Fallon. Our weather planner can help you explore destinations with more pleasant weather conditions.

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• January
• February
• March
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• May
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• September
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For a detailed overview over the year and the best time to visit the United States of America, check out our O'Fallon's climate page.

O'Fallon Temperature in January

Min Temperature -6°C (21°F)  

Max Temperature 5°C (41°F)  

Chance of Rain 23%  

Precipitation 44 mm (1.7 in)  

Rainy days 7 days  

Humidity 72% *  

Sunshine 163 hours *  

Percentage Sunshine 53% *  

* Data from: St. Louis, the United States of America (48 KM, 29 Miles).

What to Wear in O'Fallon in January

Cold weather calls for smart layering in January. A thermal base layer makes a huge difference in staying warm. Add a wool sweater or fleece, then a wind-resistant outer jacket. Rain gear is recommended, you can expect wet weather on multiple days. Bring sunglasses since you'll have some sunny periods throughout the month

What To Do in O'Fallon in January

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

5/10

Cycling

3/10

Walking

3/10

Camping

2/10

Outdoor sports

3/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit the United States of America, check out our O'Fallon's climate page.

More climate data for O'Fallon

Temperature Rainfall Sunshine Humidity

See the full O'Fallon climate overview or explore weather in the United States of America.