Williamson County (Energy)
December
Weather in Williamson County, Illinois for December 2026
Your guide to Williamson County weather in December - trends and predictions
Snowfall in Williamson County during December is quite rare, with fewer than 2 snowy days on average.
In general, the average temperature in Williamson County at the beginning of December is 2.3 °C. As the month progressed, temperatures tended to significantly warm up, reaching an average of 9.3 °C by the end of December.
With an average of 5 rainy days, Williamson County experiences minimal rainfall in December.
Is December a good time to visit Williamson County? check out the best time to travel to Williamson County page.
✨ Is December a good time to visit Williamson County? – Ask the AI Weatherman
Snow Forecast ❄️
Temperatures
Rain 🌧️
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25
Dry days
5
Rainy days
1
Snow days
7°/1°
Temperatures
21 km/h
Avg max wind
73 %
Avg humidity
Williamson County Weather December
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Temperatures trend during December in Williamson County
See the weather trend as well as the moving average line
December weather in Williamson County day by day
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| Date | Weather | Temperatures | Rain | Snow | More |
|---|---|---|---|---|---|
| Dec. 1 |  Cloudy | 1° /-4° | 0 mm | 0 cm | |
| Dec. 2 |  Overcast | 0° /-2° | 0 mm | 0 cm | |
| Dec. 3 |  Partly cloudy | 3° /-5° | 0 mm | 0 cm | |
| Dec. 4 | Overcast | 2° /-4° | 0 mm | 0 cm | |
| Dec. 5 |  Sunny | 3° /-7° | 0 mm | 0 cm | |
| Dec. 6 | Partly cloudy | 3° /-4° | 0 mm | 0 cm | |
| Dec. 7 | Sunny | 6° /-2° | 0 mm | 0 cm | |
| Dec. 8 | Overcast | 5° /0° | 0 mm | 0 cm | |
| Dec. 9 |  Light rain | 10° /4° | 4.8 mm | 0 cm | |
| Dec. 10 | Overcast | 8° /0° | 0 mm | 0 cm | |
| Dec. 11 | Partly cloudy | 5° /-1° | 0 mm | 0 cm | |
| Dec. 12 | Sunny | 8° /-1° | 0 mm | 0 cm | |
| Dec. 13 | Overcast | 7° /0° | 0 mm | 0 cm | |
| Dec. 14 |  Heavy rain | 5° /-3° | 27 mm | 0 cm | |
| Dec. 15 | Overcast | 9° /0° | 0 mm | 0 cm | |
| Dec. 16 |  Moderate rain | 10° /4° | 20.5 mm | 0 cm | |
| Dec. 17 |  Patchy rain possible | 10° /3° | 0.1 mm | 0 cm | |
| Dec. 18 | Moderate rain | 7° /2° | 22.5 mm | 0 cm | |
| Dec. 19 | Overcast | 4° /-2° | 0 mm | 0 cm | |
| Dec. 20 | Cloudy | 7° /0° | 0 mm | 0 cm | |
| Dec. 21 | Overcast | 7° /0° | 0 mm | 0 cm | |
| Dec. 22 | Patchy rain possible | 7° /1° | 0.1 mm | 0 cm | |
| Dec. 23 | Light rain shower | 10° /6° | 0.4 mm | 0 cm | |
| Dec. 24 |  Fog | 13° /8° | 0 mm | 0 cm | |
| Dec. 25 | Light rain | 14° /9° | 6.4 mm | 0 cm | |
| Dec. 26 | Patchy rain possible | 11° /7° | 1.3 mm | 0 cm | |
| Dec. 27 | Moderate rain | 11° /5° | 17 mm | 0 cm | |
| Dec. 28 | Light rain | 11° /9° | 6 mm | 0.2 cm | |
| Dec. 29 |  Light snow | 5° /2° | 21.2 mm | 1.1 cm | |
| Dec. 30 | Overcast | 7° /1° | 0 mm | 0 cm | |
| Dec. 31 | Overcast | 6° /0° | 0 mm | 0 cm | |
| Next | |||||
Important Notice
Our weather forecast for Williamson County in December is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Williamson County forecast closer to your planned date for the most up-to-date weather information.
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Williamson County in December - FAQ
What are the expected maximum and minimum temperatures in Williamson County during December?
Prepare for cooler days with highs just around 7° and colder nights, dipping below 1°.
How much rainfall should be expected in Williamson County during December?
Significant rainfall exceeding 127.2 mm is expected in Williamson County during December, occurring over more than 5 days. Preparing for wet conditions is recommended in your planning.
Will it snow in Williamson County in December 2026?
Williamson County typically sees 1.3 cm of snowfall during December.
What are the typical wind conditions in Williamson County during December?
The average wind speed in Williamson County during December is 21 km/h, suggesting breezy to windy conditions, depending on your activities.
Williamson County snow forecast December 2026
Track daily snowfall levels and discover Williamson County’s snowy potential this December ❄️
On average, Williamson County sees 1 snowy days during December, with approximately 1.3 cm of total snowfall.
December rainfall patterns in Williamson County
Explore the daily rainfall trends and prepare for Williamson Countys December weather 💧
Typically, Williamson County has 5 rainy days in December with a total of 127.2 mm of rainfall.
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