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Weather on December 21

Rockford, IL

55 Years of Data

Avg High
32°F
Avg Low
17°F
Warmest
2015
45°F avg
Coldest
1989
-12°F avg

About This Date

December 21st in Rockford, IL typically brings cold winter weather, with average highs around 32°F and lows near 17°F. Over 55 years of records, the warmest December 21st was in 2015 (45°F average), while the coldest was 1989 (-12°F) — a 57°F range across recorded history. Precipitation has occurred on 29% of recorded December 21st dates, with snow falling 22% of the time (heaviest snowfall: 4.6"). The last decade has been 8.8°F warmer on this date compared to 20-30 years ago.

The last decade has been 8.8°F warmer on this date compared to 20-30 years ago.

Planning for December 21st in Rockford, IL? Bundle up with warm layers and protect extremities from the cold. Check road conditions if traveling, as snow is possible.

Warming Trend
1.9°F per decade on this date
YearHighLowAvgPrecipSnow
202531°12°21°
202422°13°
202343°33°38°
202230°18°
202139°18°29°
202047°33°40°
201948°24°36°
201835°28°32°
201739°26°33°0.15"0.1"
201636°17°27°
2015warmest50°40°45°1.6"
201437°31°34°0.1"
201333°25°29°0.05"0.1"
201230°15°23°
201139°32°36°0.08"
201034°18°26°0.03"
200927°24°25°0.1"0.5"
2008-8°-1°
200736°34°35°
200649°37°43°1.52"
200515°
200429°19°0.03"0.3"
200349°25°37°
200233°25°29°
200139°19°29°
200016°-9°0.03"0.7"
199911°-3°
199830°18°
199735°18°26°
199634°18°26°
199529°18°23°
199442°26°34°
199327°21°24°0.03"0.3"
199236°16°26°
199134°25°29°
199038°18°28°0.33"0.6"
1989coldest-6°-18°-12°
198837°22°29°
198736°21°28°
198639°18°28°
198517°-8°
198449°30°39°0.51"
198322°15°18°0.76"4.6"
198234°14°24°
198133°23°28°0.18"0.7"
198020°10°
197942°27°34°
197825°13°19°
197728°19°24°0.2"1.2"
197613°-2°
197532°14°23°
197431°19°0.13"0.7"
197316°-8°
197233°31°32°
197136°23°29°
55 years of data from ROCKFORD GTR ROCKFORD AP

Rockford, IL Temperature Range by Month

Average monthly highs and lows. The shaded band shows the typical daily temperature range.

0°20°40°60°80°JFMAMJJASOND
Avg high Avg low

Rockford, IL Monthly Precipitation

Average rainfall and snowfall per month, in inches.

0"5.9"11.8"JFMAMJJASOND1.5"0"
Rain (in) Snow (in)

Rockford, IL Daily Temperature Calendar

Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.

151015202531JanFebMarAprMayJunJulAugSepOctNovDec
Cooler
Hotter
20°40°60°80°100°

Best Time to Visit Rockford, IL

Rockford, IL has no months that meet our "pleasant" threshold — every season has tradeoffs.

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Pleasant (65-82°F, ≤2.5" rain) Mild Less ideal

Browse Weather History

Weather data provided by NOAA Climate Data Online. Not for critical planning.

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