Galesburg weather in December

In December, Galesburg sees average daytime highs of 37°F and overnight lows near 23°F, with 2.1 in of precipitation across 7.1 wet days and about 9.1 hours of daylight. It is the 10th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 41°F in the first days to 34°F by the end. The sky is clear or mostly clear about 25% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 18 min at the start of December to 9 h 06 min by month's end. Set against the rest of the year, December is Galesburg's 11th-clearest and 6th-windiest month. For the whole year in context, see Galesburg's year-round climate.

Daytime high
37°
10th warmest
Overnight low
23°
3rd coldest
Precipitation
2.1 in
7.1 wet days
Daylight
9 h 06 min
7:25 AM – 4:30 PM
Cloud cover
66%
11th clearest
Wind
9 mph
6th windiest
Solar energy
1.75 kWh/m²
Travel score
0.0
out of 10

Galesburg is county seat of Knox County, Illinois, United States.

Density
674/km²
people per km²
Founded
1837

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 41°F in the first days to 34°F by the end.

A typical December day in Galesburg reaches about 37°F in the afternoon and slips back to 23°F overnight — a 14°F spread between the day's warmth and the night's chill. On most days the high lands between 22°F and 51°F. Set against its neighbours, December runs about 12°F cooler than November and about 5°F warmer than January.

20°40°60°151015202531
Avg high (°F)Avg low (°F)
14227
24127
34026
44026
54026
63925
73925
83824
93824
103824
113724
123723
133723
143723
153623
163623
173622
183622
193522
203522
213522
223522
233521
243521
253521
263421
273421
283420
293420
303420
313320

How December really feels in Galesburg

Once humidity and wind are folded in, December averages 0 days that feel above 90°F and 31 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
31
20 feel bitter (≤ 14°F)

The story in December is cold — wind chill drags the overnight "feels like" below the raw low.

Galesburg weather by month

How December compares with the rest of the year at a glance. December is the 10th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan32° / 17°2.07.85.29.40.0
Feb36° / 21°2.07.14.310.40.0
Mar49° / 31°2.910.12.211.71.9
Apr61° / 42°4.4120.713.14.7
May71° / 53°4.713.2014.36.1
Jun80° / 63°4.711.6014.96.2
Jul83° / 66°3.59.6014.65.8
Aug82° / 64°3.39.4013.66.5
Sep76° / 56°3.48.5012.37.2
Oct63° / 44°2.98.70.210.95.7
Nov48° / 33°2.67.71.29.72.0
Dec37° / 23°2.17.13.69.10.0

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 25% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 12% of December, with mostly cloudy or overcast conditions the remaining 63%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14060
24060
34060
43961
53961
63961
74060
84060
94060
104060
114060
123961
133961
143862
153763
163763
173763
183763
193664
203466
213466
223466
233466
243466
253466
263367
273367
283367
293367
303367
313466

Chance of precipitation in December

Any precipitationSnow

Galesburg gets around 2.1 in of rain and snow over 7.1 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 23% and peaks near 26% on the wettest days, and about 4 days bring snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1269
22510
32510
42510
52411
62411
72411
82311
92311
102311
112311
122311
132311
142311
152311
162311
172311
182311
192311
202311
212311
222311
232311
242311
252311
262312
272312
282312
292312
302313
312313

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

Most of December feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, December lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
1991
2991
3991
4991
5991
6991
7991
8991
9991
10991
11991
12991
131000
141000
151000
161000
171000
181000
191000
201000
211000
221000
231000
241000
251000
261000
271000
281000
291000
301000
311000

Wind in December

Winds average 9 mph in December.

Across December, daily wind ranges from about 9 mph on the calmest days to 9 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
19light breeze
29light breeze
39light breeze
49light breeze
59light breeze
69light breeze
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
199light breeze
209light breeze
219light breeze
229light breeze
239light breeze
249light breeze
259light breeze
269light breeze
279light breeze
289light breeze
299light breeze
309light breeze
319light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 18 min at the start of December to 9 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 12 minutes over December. Sunrise moves from 7:13 AM to 7:32 AM, and sunset from 4:29 PM to 4:37 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.37:134:29
29.37:144:29
39.27:154:29
49.27:164:29
59.27:174:29
69.27:184:29
79.27:194:29
89.27:194:29
99.17:204:29
109.17:214:29
119.17:224:29
129.17:234:29
139.17:234:29
149.17:244:29
159.17:254:30
169.17:254:30
179.17:264:30
189.17:274:30
199.17:274:31
209.17:284:31
219.17:284:32
229.17:294:32
239.17:294:33
249.17:304:33
259.17:304:34
269.17:304:34
279.17:314:35
289.17:314:35
299.17:314:36
309.17:324:37
319.17:324:37

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 1.75 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 1.75 kWh/m² to a high of 6.41 kWh/m² in June across the year — December's 1.75 kWh/m² sits near the bottom.

00.511.522.5151015202531
Solar energy (kWh/m²)Level
11.8Dim
21.8Dim
31.8Dim
41.8Dim
51.8Dim
61.8Dim
71.8Dim
81.8Dim
91.8Dim
101.8Dim
111.8Dim
121.8Dim
131.8Dim
141.7Dim
151.7Dim
161.7Dim
171.7Dim
181.7Dim
191.7Dim
201.7Dim
211.7Dim
221.7Dim
231.7Dim
241.7Dim
251.7Dim
261.7Dim
271.8Dim
281.8Dim
291.8Dim
301.8Dim
311.8Dim
Planning a trip in December

Is December a good time to visit Galesburg?

Our two travel scores rate December for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

0.0
Sightseeing
10th-best month of the year
0.0
Beach & pool
10th-best month of the year

December is a weaker month for outdoor sightseeing in Galesburg.

What to pack for Galesburg in December

From December's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In December, Galesburg sees daytime highs around 37°F and nights near 23°F. Pack a warm layer and a heavy coat. About 7 days see rain.

a warm layera heavy coat

UV index in Galesburg in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 2. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Galesburg peaks around June 19 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJun 19UV 9Dec 21UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug8Very high
Sep7High
Oct4Moderate
Nov3Moderate
Dec2Low

Air quality in Galesburg in December

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where December falls, not just the annual average.

Air quality in Galesburg is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (October, 8 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodJul 1915 µg/m³Oct 228 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb13Moderate
Mar13Moderate
Apr11Good
May13Moderate
Jun13Moderate
Jul16Moderate
Aug15Moderate
Sep11Good
Oct8Good
Nov8Good
Dec9Good
Location & terrain

Where is Galesburg?

Galesburg sits at 40.9°N, 90.4°W, 771 ft above sea level, in United States. The nearest listed city is Macomb, 37 mi away.

Topography around Galesburg

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Galesburg.

Within 2 miles, the terrain around Galesburg has only modest variations in elevation — a maximum elevation change of 75 ft around an average of 778 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 259 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 528 ft.

The land around Galesburg is covered by artificial surfaces (31%), trees (26%) and grassland (22%) within 2 miles, cropland (67%) and trees (21%) within 10 miles, and cropland (68%) and trees (21%) within 50 miles.

2 miles
75 ft
10 miles
259 ft
50 miles
528 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: Macomb 37 mi · East Moline 39 mi · Moline 39 mi · Burlington 40 mi · Rock Island 40 mi · Bettendorf 40 mi · Davenport 41 mi · North Peoria 44 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Galesburg (40.9478°, -90.3712°, elevation 771 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).