The highest day temperature in December 2025 was 48°F. The lowest night temperature was -8°F. The average values for day and night temperatures during December were 26.8°F и 18.2°F respectivly.

Most of the days in December are gloomy but you can also expect sunny days.

Precipitation total in December for Rockford is 0.6 in. It makes december one of the least rainy months of the year.

The average wind speed in December is 9.7 mph.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Rockford in December is 4.0 hours.